In order to follow someone on Pinterest, search out the person to follow using the search bar, and click "follow" on his or her profile page. This will automatically enable the following of all existing and new boards a user adds to their profile.
When a user wants to follow another person on Pinterest, they have the option of following the complete profile or only following a certain board. To follow the entire profile, navigate to the profile of the specific user and click the red follow button on the upper right side of the screen. To follow only a specific board, click on the board to open it, and then on the red follow button at the upper right side of the page.