Click on what you want to change (for example hair or teacup), then click on the teapots to change the item. Sometimes there are arrows and color options too!
Once you're mastered how to play this game, it is quite beautiful! I'm a big fan of extras in dress-up games so I really love the teacups, the yummy cakes, and all the backgrounds! I think I'll go to a cafe later and buy myself a treat!