How do I change my sims appearance once game has started...i am new to Sims3 plz help

send your sim to a mirror option change apperance this will allow you to change hair and make up send your sim to a dressser-plan outfit there you can change the outfits or add a new outfit onc ethe outfit is the one you want tick accept this will close the CAS (create a style  )so for example  if you give your sim two every day outfits then you click on your sim change outfit a pop up will appear with the list of the clothes click the one you want everyday 1 everday 2 and your sim will spin and change to the outfit you selected