To create a new topic folder, begin by navigating to the topic management screen, which can be done in any of three ways.
1 - By clicking "manage" above the topic list on the filter menu on the left of the screen. [NOTE: This view isn't available on mobile]
2 - By clicking on "manage my topics" at the top of the drop-down topic menu from the main navigation bar.
3 - By clicking into your account menu, then selecting, "Topics".
Once you are on the topic management screen, click on "Add Folder"
Note: Each user is given a default folder called, "Active". Topics in this folder will always appear in your side-bar and drop-down view for topics.
You can also add new folders inside of folders by clicking on "Add Folder" next to the appropriate folder. There is no limit to how many folders you can add inside of folders.