There are many links about this on the Welcome board that is set up for questions. Many are asking about this too, and I'm sorry it's confusing.
For now, only CL's and CM's could have an avatar besides the "preset" ones in the profile box. They may expand that later for all the members to upload "personal" ones.
1) If you haven't already, Log in
2) Click on Your Profile (link is at the very top of the board header). This will open up your Profile.
3) Click on "update your profile".
4) You now have five (5) tabs:
* WHO I AM * ADD IMAGE * WHAT I LIKE * MORE ABOUT ME * FRIENDS
Click on ADD IMAGE.
You will see several that you can choose from. Choose one, and click "submit". You can choose what ever other fields within the profile that you want to answer. The only ones that will show are the ones you fill in and "submit". While you're in there, be sure to click on board settings, and click the email option "off", for your safety and privacy.
I hope this helps, and hope you have a great day Cherry!