Load up Google MapMaker and click on the Gear icon, then click My Profile
Change the display name:
Once you're in the profile page, click Edit Nickname to bring up the following dialog box:
Change the display photo:
Within this profile page, you can click Edit Photo to choose a new profile picture to be shown in MapMaker. As of February 2013, there is only an option to upload a new photo to a new album.
Mapping Tutorials >