Hey and welcome! I'm Natalia
To answer your question, take a look at this post which can be found in the New Members Guide and FAQs
QUOTE(karmakiller @ Apr 27 2009, 09:33 PM)
How do I customize my avatar?
Click on "My Controls", from there click "Edit Avatar Settings" (found on the left-hand side under the title: Personal Profile
.) Then upload your own avatar, or use one preset by cB. If your avatar is too big for CB to host, then upload it to a site like TINYPIC
Hope it helps and if you're still lost, don't hesitate to let me know!