If you connect your Slack account, we'll pull in your profile photo from Slack and automatically keep it synced.
If you'd like to add a custom profile photo, you can do so from your My Profile page.
Simply click the "upload new avatar" button, select the file, and then "Save changes".
This will return your personal avatar to your original slack-synced avatar. If you don't have one, it will return the avatar to the default Tettra logo.