Miui 8 - Oppo F1s

: The device bootloader must be unlocked to permit the installation of custom software.

The installation follows a standard custom ROM flashing procedure: How do I want to upgrade my Oppo F1 s? miui 8 oppo f1s

: You must have a custom recovery like Team Win Recovery Project (TWRP) installed. : The device bootloader must be unlocked to

: Charge your phone to at least 100% to prevent it from powering off mid-process. as all data will be wiped.

: Create a complete system backup via TWRP, as all data will be wiped.