pag meron kanang TWRP/CWM (custom recovery installed or flashed sa device),
boot into recovery
wipe dalvik/cache
backup
select storage to save (internal or external)
once complete
reboot system
how to restore
boot into recovery
wipe dalvik/cache
restore
select storage where you saved your backup (internal or external)
once complete
reboot system
note:
a folder with name TWRP/CWM will be created depending on storage where you chose to save your back up rom, inside TWRP/CWM will be another folder named Backup and inside backup would be another folder with date and name of your back up rom
via custom recovery kalang makakagawa ng backup roms na pwede irestore anytime, unless gagawa ka sa cygwin kitchen(android kitchen) at gumawa ng flashable zip rom
or download nalang ng stock rom or update rom sa official site ng device para pwede mo install/flash pag nagkaproblema