and how do i put an i image at my signature?

ok thanks but i have another question can u make a commentary with lolreplay?

You can either share them via LoL Replay's sharing service (requires a login) or you can go to a file sharing service, upload it, and post the link somewhere.

thanks and how do i upload them?(i wont but so i know)

Just leave it running at the same time as playing a game and it'll record your games.