The first is to use this link: »/forums/all?ch ··· choose=1
On the subsequent page, you may simply select your favorites by checking the box and saving the page. To remove a forum from your favorites just return to the page and remove the check, remembering to click on the save button.
Another method is to click on the "About" link at the top of the forum. This will take you to a page where you can designate the forum as one of your favorites.
This takes you to a page where you can make the forum one of your favorites by using the link pictured below: