The Players' Guide to the Cities/User Interface/Costume Window
The Costume Window may be opened by selecting "Costume" from the Menu Window.
In this window you will see all of the costume slots you have unlocked, and will be able to switch between costumes for your character's avatar. The costume you are currently wearing will be lit in the window. Any costume slots you have not unlocked will be blacked out with a '?' in the middle. Costumes you have unlocked that are not currently active will be shaded over. To change costumes, simply click on the shaded costume slot you wish to activate. You must then wait at least 30 seconds before changing costumes again.
Costume change emotes are incorporated on a pull tab in the center of the display towards the bottom. Simply select what emote you would like to execute and then select to which costume to change into.