Your campus selector is located in your navigation as the "locations" option. When you click on locations, it will display the campus selector with all the campus and map information. 

To edit the locations or add new ones, you will go to People > Branches in the CMS. You will add the number before the name without a space to tell the campus what order to display in. You will also need to add the "Actual Title" which will tell it how to display on the website. 

The website field will link the user to the page that the "details" button or "visit campus page" button links to. You can add service times to the description field, and a Pastor name to the Pastor field.