Default [Q] i want help backing up stock rom lg p999

hey xda members
first of all to the mods i am sorry if this is in the wrong section i am new to this fourms

so i bought a 2nd hand lg-p999-optimus G2X wind mobile variant (canada) and i know that alot of people need this rom for various reasons so now i want to back it up and uploaded to xda so what the best way to do it

thanks in advance