You can belong to as many chapters as you'd like. It's easy to subscribe or unsubscribe to a chapter from within your Account Settings.
Log into your account, hover over your profile image in the top right, and select My Account.
Scroll down to Chapter Memberships where you can see the chapters in which you're already a member (see the city and a checkbox):
To select additional chapters, click on the dropdown menu Select New Chapter and click on the city you'd like to subscribe to:
(Optional) If you want to unsubscribe from a chapter, simply uncheck the box next to the city name:
Once you're ready, click on Update Chapter Memberships to save the changes.