The Builderall dashboard profile picture is managed by a free service called Gravatar.  To change your profile picture for the dashboard, go to the top menu in the Builderall dashboard and choose "Account"

And then choose "Advanced Configurations"

In the Account Info area on the general tab, click the icon that is in the corner of your profile image

This will take you to Gravatar where you can create a new account, connect it to the Builderall dashboard, and manage your profile image.

NOTE:  If you do not have a Gravatar account, create a new one for free and then follow the instructions to add your image to your Builderall dashboard profile.