Hello and Welcome to the 'Z' from the beautiful Shenandoah Valley of Virginia. :wavey: Enjoy your Ride and the Site! You'll find some knowledgeable and friendly people to answer your questions or just entertain you. Glad you could join us!
To add an avatar, go up yo User CP on the top left tool bar and go to edit your avatar. You do have picture size restrictions.
BTW, tell us a little about yourself and your Challenger.
Welcome to the forum...With respect to your question of "how", I believe there is a thread or two on the process. I just asked a moderator this morning on parameters to posting a pic in the signature line and was provided this link: