Hi kaity_sims_lover, new members need to have 5 posts before they can edit their profile pages. This is to help curb spamming. Once you have 5 posts you can click your username to edit your profile. Modify Profile > Forum Profile.
I'm sure you'll be at 5 posts in no time at all.
*edited: Opps MrsFlynn! I posted at the same time as you. I like your in-depth explanation much better than mine though!