Install LineageOS on hydrogen

Basic requirements

Important: Please read through the instructions at least once completely before actually following them to avoid any problems because you missed something!

Make sure your computer has working adb. Setup instructions can be found here.
Enable USB debugging on your device.

Unlocking the bootloader

Note: The steps below only need to be run once per device.

Warning: Unlocking the bootloader will erase all data on your device! Before proceeding, ensure the data you would like to retain is backed up to your PC and/or your Google account, or equivalent.

Visit Xiaomi’s official unlocking website.
Apply for unlocking permissions.
Download the Mi Unlock app.
Wait patiently until you get the approval, which may take some days.
Once you get the approval, run the Mi Unlock app and follow the instructions provided by the app.
After device and Mi account are sucessfuly verified, the bootloader should be unlocked.
Since the device resets completely, you will need to re-enable USB debugging to continue.

Tip: A Mi account is required to apply for permissions. You don’t need to re-apply for permissions to unlock new devices, but beware that one account is only allowed to unlock one unique device every 30 days.

Tip: It is highly recommended to have the latest official MIUI dev package installed on the device, before proceeding with unlock.

Installing a custom recovery using `fastboot`

Download recovery - visit twrp.me to obtain the latest version of Team Win Recovery Project for your device.
Connect your device to your PC via USB.
Open a terminal on the PC and boot the device to fastboot mode by typing:
```
 adb reboot bootloader
```
You can also boot into fastboot mode via a key combination:
- Hold Volume Down and Power buttons simultaneously. Continue to hold both buttons until the word “FASTBOOT” appears on the screen, then release.
Once the device is in fastboot mode, verify your PC finds it by typing:
```
 fastboot devices
```
If you see no permissions fastboot or <waiting for device>, try running fastboot as root/Administrator.

Flash recovery onto your device:

 fastboot flash recovery your_recovery_img.img

Now reboot into recovery to verify the installation:
- Hold Volume Up and Power buttons simultaneously. Continue to hold both buttons until the “MI” logo appears on the screen, then release.

Installing LineageOS from recovery

Download the LineageOS install package that you’d like to install or build the package yourself.
- Optionally, download 3rd party application packages like Google Apps
Place the LineageOS .zip package, as well as any other .zip packages on the root of /sdcard:
- Using adb: adb push filename.zip /sdcard/
- You can use any method you are comfortable with. adb is universal across all devices, and works both in Android and recovery mode, providing USB debugging is enabled.
If you aren’t already in recovery, boot into recovery:
- Hold Volume Up and Power buttons simultaneously. Continue to hold both buttons until the “MI” logo appears on the screen, then release.
(Optional, but recommended): Select the Backup button to create a backup.
Select Wipe and then Advanced Wipe.
Select Cache, System and Data partitions to be wiped and then Swipe to Wipe.
Go back to return to main menu, then select Install.
Navigate to /sdcard, and select the LineageOS .zip package.
Follow the on-screen prompts to install the package.
(Optional): Install any additional packages using the same method.
Note: If you want any Google Apps on your device, you must follow this step before the first reboot!
(Optional): Root the device by installing the LineageOS su add-on (use the arm64 package) or using any other method you prefer.
Once installation has finished, return to the main menu, select Reboot, and then System.

Get assistance

If you have any questions, or get stuck on any of the steps, feel free to ask on our subreddit, or in #LineageOS on freenode.