How to Install a Custom ROM

This is the moment you've been preparing for. All that bootloader unlocking and recovery installing has led here.

I've flashed hundreds of ROMs over the years, and I'm going to walk you through exactly how I do it. Follow these steps, and you'll be running your new ROM in under 30 minutes.

Before We Start

Prerequisites Checklist

Make sure you've completed these:

Bootloader is unlocked - If not, start here
Custom recovery installed - TWRP guide
Full backup made - Backup guide
Battery above 50% - Seriously, don't flash on low battery
All files downloaded - ROM, GApps, Magisk (if wanted)

Files You Need

📁 Download folder (on phone):
├── ROM.zip (e.g., lineage-21.0-xxx-device.zip)
├── GApps.zip (if ROM doesn't include Google apps)
└── Magisk.zip (optional, for root)

Where to get these:

ROM: Official ROM website or XDA
GApps: NikGapps or MindTheGapps
Magisk: GitHub Releases

Step 1: Transfer Files to Phone

If files aren't already on your phone:

# Via ADB
adb push lineage-21.0-xxx.zip /sdcard/Download/
adb push NikGapps-xxx.zip /sdcard/Download/

Or just copy via USB file transfer before booting to recovery.

Pro tip: Keep files in a simple path with no spaces. /sdcard/Download/ is perfect.

Step 2: Boot into Recovery

Option A: Via ADB

adb reboot recovery

Option B: Button Combo

Power off completely, then:

Brand	Combo
Most Android	Power + Volume Up
Samsung	Power + Volume Up + Bixby
Xiaomi	Power + Volume Up
OnePlus	Power + Volume Down → Select Recovery

Step 3: Backup in Recovery (Recommended)

If you haven't already, backup now:

TWRP Main Screen → Backup
Select:
- Boot ✓
- System ✓
- Vendor ✓
- Data (optional, takes time)
Swipe to backup

This is your safety net if anything goes wrong.

Step 4: Wipe for Clean Install

This is critical. Most ROM installation issues come from not wiping properly.

Standard Wipe

TWRP → Wipe → Advanced Wipe
Select:
- Dalvik / ART Cache ✓
- System ✓
- Data ✓
- Cache ✓

⚠️ DO NOT SELECT "Internal Storage" - you'll lose your downloaded files!

Swipe to wipe

When to Format Data Instead

If you're:

Coming from a different ROM base (e.g., MIUI to AOSP)
Having encryption issues
Doing a completely fresh start

TWRP → Wipe → Format Data
Type "yes"
Confirm

Warning: Format Data also wipes internal storage. Make sure files are backed up elsewhere.

Step 5: Flash the ROM

Here's the exciting part:

TWRP → Install
Navigate to your ROM zip
Tap to select
Swipe to confirm flash

Wait for it...

You'll see installation progress. This takes 1-5 minutes depending on ROM size.

Look for: "Successful" at the end.

Don't Reboot Yet!

If you have more files to flash, stay in recovery.

Step 6: Flash GApps (If Needed)

Many ROMs don't include Google apps. If yours doesn't (check ROM description), flash GApps now:

TWRP → Install
Select GApps zip
Swipe to flash
Wait for success

Critical: Always flash GApps before first boot! Adding them later often causes issues.

Step 7: Flash Magisk (Optional - For Root)

Want root access?

TWRP → Install
Select Magisk zip
Swipe to flash
Wait for success

Step 8: Clear Cache and Reboot

Almost done:

TWRP → Wipe → Wipe Cache/Dalvik
Swipe to wipe

Then:
TWRP → Reboot → System

Step 9: First Boot

The first boot takes longer than normal. Don't panic!

Expect 5-10 minutes
Screen might show boot animation for a while
Android is optimizing apps in the background

If you're still on boot animation after 15-20 minutes, something went wrong. See troubleshooting below.

Step 10: Initial Setup

Once you're in:

1. Select language
2. Connect to WiFi
3. Sign into Google (if you have GApps)
4. Restore apps from backup (optional)
5. Configure settings
6. Enjoy your new ROM! 🎉

Troubleshooting

Bootloop (Stuck on Boot Animation)

Causes:

Wrong ROM for your device
GApps incompatibility
Incomplete wipe

Fix:

1. Boot back to recovery
2. Wipe Data again
3. Reflash ROM + GApps
4. If still failing, try different GApps package
5. Last resort: try different ROM

No WiFi or Mobile Data

Cause: Firmware/vendor mismatch

Fix:

1. Check ROM's XDA thread for firmware requirements
2. Flash matching firmware before ROM
3. Reflash ROM after firmware

"No OS Installed" Error

Cause: ROM flash failed

Fix:

1. Wipe System, Cache, Dalvik
2. Reflash ROM
3. Verify ROM is for your exact device variant

Google Apps Force Closing

Cause: Incompatible GApps package

Fix:

1. Use different GApps variant (try Core or Basic)
2. Make sure GApps matches your Android version
3. Clean flash ROM + GApps

Encryption Issues

Cause: Different encryption format from previous ROM

Fix:

TWRP → Wipe → Format Data → type "yes"
This decrypts and wipes data completely
Then flash ROM fresh

Clean Flash vs Dirty Flash

Clean Flash (what we just did):

Wipes System and Data
Required when switching ROMs
Required for major updates

Dirty Flash (preserves data):

Wipes only System
Works for minor updates within same ROM
Keeps all your apps and settings

Learn more about dirty flashing

Post-Installation Tips

First Things to Do

Check everything works: WiFi, Bluetooth, camera, GPS, calls
Update apps through Play Store
Set up backup solution for the future
Join ROM's community (Telegram/Discord) for support

If Something Doesn't Work

Check ROM's XDA thread for known issues
Ask in ROM's Telegram group
Try searching "[ROM name] [issue]" on Google
Flash a known fix if available

Summary

Installation Flowchart:

Transfer files to phone
        ↓
Boot to TWRP recovery
        ↓
Backup (if not done)
        ↓
Wipe: Dalvik, System, Data, Cache
        ↓
Flash ROM → Flash GApps → Flash Magisk
        ↓
Wipe Cache/Dalvik
        ↓
Reboot → Wait for first boot
        ↓
Setup and enjoy!

You've done it! Welcome to the custom ROM world. Every phone feels new again with a fresh ROM.

If you need help, check our troubleshooting guide or join the community. Happy flashing!

Keywords: install custom rom, flash custom rom, twrp flash rom, android rom installation, how to flash rom

How to Install a Custom ROM

This is the moment you've been preparing for. All that bootloader unlocking and recovery installing has led here.

I've flashed hundreds of ROMs over the years, and I'm going to walk you through exactly how I do it. Follow these steps, and you'll be running your new ROM in under 30 minutes.

Before We Start

Prerequisites Checklist

Make sure you've completed these:

Bootloader is unlocked - If not, start here
Custom recovery installed - TWRP guide
Full backup made - Backup guide
Battery above 50% - Seriously, don't flash on low battery
All files downloaded - ROM, GApps, Magisk (if wanted)

Files You Need

📁 Download folder (on phone):
├── ROM.zip (e.g., lineage-21.0-xxx-device.zip)
├── GApps.zip (if ROM doesn't include Google apps)
└── Magisk.zip (optional, for root)

Where to get these:

ROM: Official ROM website or XDA
GApps: NikGapps or MindTheGapps
Magisk: GitHub Releases

Step 1: Transfer Files to Phone

If files aren't already on your phone:

# Via ADB
adb push lineage-21.0-xxx.zip /sdcard/Download/
adb push NikGapps-xxx.zip /sdcard/Download/

Or just copy via USB file transfer before booting to recovery.

Pro tip: Keep files in a simple path with no spaces. /sdcard/Download/ is perfect.

Step 2: Boot into Recovery

Option A: Via ADB

adb reboot recovery

Option B: Button Combo

Power off completely, then:

Brand	Combo
Most Android	Power + Volume Up
Samsung	Power + Volume Up + Bixby
Xiaomi	Power + Volume Up
OnePlus	Power + Volume Down → Select Recovery

Step 3: Backup in Recovery (Recommended)

If you haven't already, backup now:

TWRP Main Screen → Backup
Select:
- Boot ✓
- System ✓
- Vendor ✓
- Data (optional, takes time)
Swipe to backup

This is your safety net if anything goes wrong.

Step 4: Wipe for Clean Install

This is critical. Most ROM installation issues come from not wiping properly.

Standard Wipe

TWRP → Wipe → Advanced Wipe
Select:
- Dalvik / ART Cache ✓
- System ✓
- Data ✓
- Cache ✓

⚠️ DO NOT SELECT "Internal Storage" - you'll lose your downloaded files!

Swipe to wipe

When to Format Data Instead

If you're:

Coming from a different ROM base (e.g., MIUI to AOSP)
Having encryption issues
Doing a completely fresh start

TWRP → Wipe → Format Data
Type "yes"
Confirm

Warning: Format Data also wipes internal storage. Make sure files are backed up elsewhere.

Step 5: Flash the ROM

Here's the exciting part:

TWRP → Install
Navigate to your ROM zip
Tap to select
Swipe to confirm flash

Wait for it...

You'll see installation progress. This takes 1-5 minutes depending on ROM size.

Look for: "Successful" at the end.

Don't Reboot Yet!

If you have more files to flash, stay in recovery.

Step 6: Flash GApps (If Needed)

Many ROMs don't include Google apps. If yours doesn't (check ROM description), flash GApps now:

TWRP → Install
Select GApps zip
Swipe to flash
Wait for success

Critical: Always flash GApps before first boot! Adding them later often causes issues.

Step 7: Flash Magisk (Optional - For Root)

Want root access?

TWRP → Install
Select Magisk zip
Swipe to flash
Wait for success

Step 8: Clear Cache and Reboot

Almost done:

TWRP → Wipe → Wipe Cache/Dalvik
Swipe to wipe

Then:
TWRP → Reboot → System

Step 9: First Boot

The first boot takes longer than normal. Don't panic!

Expect 5-10 minutes
Screen might show boot animation for a while
Android is optimizing apps in the background

If you're still on boot animation after 15-20 minutes, something went wrong. See troubleshooting below.

Step 10: Initial Setup

Once you're in:

1. Select language
2. Connect to WiFi
3. Sign into Google (if you have GApps)
4. Restore apps from backup (optional)
5. Configure settings
6. Enjoy your new ROM! 🎉

Troubleshooting

Bootloop (Stuck on Boot Animation)

Causes:

Wrong ROM for your device
GApps incompatibility
Incomplete wipe

Fix:

1. Boot back to recovery
2. Wipe Data again
3. Reflash ROM + GApps
4. If still failing, try different GApps package
5. Last resort: try different ROM

No WiFi or Mobile Data

Cause: Firmware/vendor mismatch

Fix:

1. Check ROM's XDA thread for firmware requirements
2. Flash matching firmware before ROM
3. Reflash ROM after firmware

"No OS Installed" Error

Cause: ROM flash failed

Fix:

1. Wipe System, Cache, Dalvik
2. Reflash ROM
3. Verify ROM is for your exact device variant

Google Apps Force Closing

Cause: Incompatible GApps package

Fix:

1. Use different GApps variant (try Core or Basic)
2. Make sure GApps matches your Android version
3. Clean flash ROM + GApps

Encryption Issues

Cause: Different encryption format from previous ROM

Fix:

TWRP → Wipe → Format Data → type "yes"
This decrypts and wipes data completely
Then flash ROM fresh

Clean Flash vs Dirty Flash

Clean Flash (what we just did):

Wipes System and Data
Required when switching ROMs
Required for major updates

Dirty Flash (preserves data):

Wipes only System
Works for minor updates within same ROM
Keeps all your apps and settings

Learn more about dirty flashing

Post-Installation Tips

First Things to Do

Check everything works: WiFi, Bluetooth, camera, GPS, calls
Update apps through Play Store
Set up backup solution for the future
Join ROM's community (Telegram/Discord) for support

If Something Doesn't Work

Check ROM's XDA thread for known issues
Ask in ROM's Telegram group
Try searching "[ROM name] [issue]" on Google
Flash a known fix if available

Summary

Installation Flowchart:

Transfer files to phone
        ↓
Boot to TWRP recovery
        ↓
Backup (if not done)
        ↓
Wipe: Dalvik, System, Data, Cache
        ↓
Flash ROM → Flash GApps → Flash Magisk
        ↓
Wipe Cache/Dalvik
        ↓
Reboot → Wait for first boot
        ↓
Setup and enjoy!

You've done it! Welcome to the custom ROM world. Every phone feels new again with a fresh ROM.

If you need help, check our troubleshooting guide or join the community. Happy flashing!

Keywords: install custom rom, flash custom rom, twrp flash rom, android rom installation, how to flash rom

How to Install a Custom ROM - Complete Step-by-Step Guide

How to Install a Custom ROM

Before We Start

Prerequisites Checklist

Files You Need

Step 1: Transfer Files to Phone

Step 2: Boot into Recovery

Option A: Via ADB

Option B: Button Combo

Step 3: Backup in Recovery (Recommended)

Step 4: Wipe for Clean Install

Standard Wipe

When to Format Data Instead

Step 5: Flash the ROM

Don't Reboot Yet!

Step 6: Flash GApps (If Needed)

Step 7: Flash Magisk (Optional - For Root)

Step 8: Clear Cache and Reboot

Step 9: First Boot

Step 10: Initial Setup

Troubleshooting

Bootloop (Stuck on Boot Animation)

No WiFi or Mobile Data

"No OS Installed" Error

Google Apps Force Closing

Encryption Issues

Clean Flash vs Dirty Flash

Post-Installation Tips

First Things to Do

If Something Doesn't Work

Summary

🎉 Found this helpful?

How to Install a Custom ROM - Complete Step-by-Step Guide

How to Install a Custom ROM

Before We Start

Prerequisites Checklist

Files You Need

Step 1: Transfer Files to Phone

Step 2: Boot into Recovery

Option A: Via ADB

Option B: Button Combo

Step 3: Backup in Recovery (Recommended)

Step 4: Wipe for Clean Install

Standard Wipe

When to Format Data Instead

Step 5: Flash the ROM

Don't Reboot Yet!

Step 6: Flash GApps (If Needed)

Step 7: Flash Magisk (Optional - For Root)

Step 8: Clear Cache and Reboot

Step 9: First Boot

Step 10: Initial Setup

Troubleshooting

Bootloop (Stuck on Boot Animation)

No WiFi or Mobile Data

"No OS Installed" Error

Google Apps Force Closing

Encryption Issues

Clean Flash vs Dirty Flash

Post-Installation Tips

First Things to Do

If Something Doesn't Work

Summary

🎉 Found this helpful?