Before you get started, do take the nandroid backup of your device. Backup your device is always important, if something goes wrong then you can restore your device easily. Once the backup is done, follow the below mention guide to installing custom ROM.
Install a Custom ROM on Your Android With TWRP Recovery
Step-1 To get started, you need a Custom ROM for your phone and Google Apps Package for your phone. For Custom do a google search and download the Gapps
Gapps
Step-2 Now move both the downloaded files on your phone internal memory.
Step-3 After this Boot your phone in recovery mode. (try googling on how to enter recovery mode.)
Step-4 Once your phone in TWRP main menu Select Wipe > Advanced wipe and Select Dalvik Cache, System, Data and Cache then swipe to wipe.
Note- Don’t Select the Internal option, otherwise you will delete the Custom ROM file and Gapps File.
Step-5 Now go back to the main menu and select the Install option. Now select the ROM files and Google apps to flash.
Install a Custom ROM on Your Android With CWM Recovery
Step-1 To get started, you need a Custom ROM for your phone and Google Apps Package for your phone. For Custom do a google search and download the Gapps for the ROM here.
Step-2 Move both the downloaded files on your phone’s internal memory.
Step-3 After this Boot your phone in recovery mode. (try googling on how to enter recovery mode.)
Step-4 Once you on the CWM recovery. Select Wipe Data/Factory Reset > Wipe All User Data > Yes
Step-5 Now go to Wipe Cache partition option in the main screen and select yes.
Step-6 Go to “install zip > choose zip from sd card”. Then browse the zip file on your internal sd card. And flash both the Files ROM and Gapps one by one on your phone.
Step-7 Now go back to the main menu, select “reboot system now”. Sometime next you can see “disable recovery flash” select that option.
Congratulation you have installed the Custom ROM on your Android smartphone.
