When you add Contacts, whether in-game or a Game Center/Facebook friend, you have the option to gift them clothing and accessories for their wardrobe. Gifting costs 
cash and 
stars. Gift prices vary from your own Kustomization wardrobes.
To gift someone, open up your contacts list and find someone you want to gift something to.
There will be a 
to tap next to your date/friend's character. It will take you to their wardrobe where you can buy something for them to give to.
If you are dating an in-game character, you will be able to unlock gifts for them based on your relationship status. Buying clothes for your date can also improve your relationship points. Note that if you are dating Dirk Diamonds or Willow Pape, you cannot gift with them.
Real-Life Friends
Tops
Template:FriendGiftables:Tops
Bottoms
Template:FriendGiftables:Bottoms
Shoes
Template:FriendGiftables:Shoes
Accessories
Template:FriendGiftables:Accessories