As long as you haven't entered your name, you'll be shown in RPLAN with your email address. You can change it on the user profile page, which is accessible via the drop-down menu next to your email address at the upper right.
You can add your first and/or last name, so that it's easier for team members and other collaborators to identify you. As default we use your initials for the avatar. They will be build automatically from your email address. But of course you can change it to your liking (up to two letters).
To change the look of your avatar you have the option enable loading your image from gravatar. If your email is not yet connected to gravatar, follow the link to gravatar.com to change it.
All changes you making in your personal data section will be saved automatically. And of course you can change it anytime.