To change up your look, tap the Profile icon at the top-left of your screen and select the clothing icon.  From The Wardrobe, you will be able to change your hair, clothes, accessories and more!
If you have selected a premium option, the total gem cost will appear in your cart.  Tap the x to empty your cart.
Once you're happy with your changes, tap the green check mark in the top-right corner.
Not feeling your new look?  Tap the back button in the top-left corner and select "Exit" to revert your changes.