To add or change a project's avatar, hover over the project name in your dashboard until the ( i ) button appears next to it. Click on the button to open the project settings.
In the settings, click on the small triangle next to the avatar field. This will open a drop-down menu where you can either choose one of the good-looking avatars from our library, or upload your own image.
If you upload your own image, it should be square and may use transparency.