Note: As some of you have noted, you don't actually need root access to flash a custom ROM - though you will need to unlock your bootloader (a process that sometimes comes bundled with root access).
Inothi: Awunayo empeleni badinga ukufinyelela impande flash a ROM ngokwezifiso, Nokho uzodinga Vula bootloader yakho (inqubo ukuthi ngezinye izikhathi iza izikhwebu nge ukufinyelela impande).