I switched classes but now I want to switch back, how do I do that?

To switch classes at any time go to the Class Hall building and tap the Class option. Then select the class you want to change to. Unless you have a class change available from reaching the set levels (10, 13, 16, 19, 22, 25) you will need to buy a class change item to complete the change though. These need to be bought with real money.