How To Android: Install ADB & Fastboot on Mac OS X
https://www.youtube.com/watch?v=jgM3yHImDR0

Use Android File Transfer to backup files you want to keep before unlocking your bootloader:
https://www.android.com/filetransfer/

SAMSUNG USERS, NOTE: This method will not work for your device(s).

Download TWRP Custom Recovery:

Nexus 6P
https://twrp.me/devices/huaweinexus6p.html

Nexus 5X
https://twrp.me/devices/lgnexus5x.html

OnePlus One (Use /”fastboot oem unlock/” instead of /”fastboot flashing unlock/”)
https://twrp.me/devices/oneplusone.html

OnePlus 2 (Use /”fastboot oem unlock/” instead of /”fastboot flashing unlock/”)
https://twrp.me/devices/oneplustwo.html

OnePlus 3 (Use /”fastboot oem unlock/” instead of /”fastboot flashing unlock/”)
https://twrp.me/devices/oneplusthree.html

OnePlus 3t (Use /”fastboot oem unlock/” instead of /”fastboot flashing unlock/” and see WARNING below!)
https://twrp.me/devices/oneplus3t.html
—-WARNING: The OnePlus 3T stock boot image has dm-verity, which prevents you from booting if you swipe to enable system modifications! Be sure to install the latest /”dm-verity and forced encryption disabler/” before choosing this option & rebooting!—-See the next video on how to install a ROM for how to install this.—
https://build.nethunter.com/android-tools/no-verity-opt-encrypt/
See this page for detailed instructions:
https://forums.oneplus.net/threads/guide-oneplus-3t-how-to-unlock-bootloader-flash-twrp-root-nandroid-efs-backup-and-more.475142/

PIXEL & PIXEL XL UPDATED Instructions:

1. On your phone, you’ll need to download two things:

-The latest TWRP zip file from here:

https://dl.twrp.me/marlin/

-Verified Boot Signer.zip from here:

https://forum.xda-developers.com/android/software-hacking/signing-boot-images-android-verified-t3600606

2. On your computer download the latest TWRP.img from here:

https://dl.twrp.me/marlin/

3. Plug your phone into your computer and use /”fastboot boot twrp.img/” instead of /”fastboot flash recovery twrp.img/”.

4. From TWRP install the TWRP zip file and then install the VBS zip. Order is important! Also, note that when you install anything new through TWRP you’ll need to flash the VBS.zip before booting so keep it on your phone!

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