There are two ways to unfollow someone on Foundation:
1. Go to the profile that you wish to unfollow and hover over the follow button. It will immediately turn red and say "Unfollow." Once you click "Unfollow," the change will take place immediately.
2. Click "Following" on your account page, scroll through the list to find the user you wish to unfollow, and click the "Unfollow" button next to their name.