Up In The Air

A: "Ugh, all my shirts got tangled up in the washing machine."
B: "How is that even possible? That just sounds like something that someone would make up for the purpose of writing a puzzle."

Looks like some of your shirts got tangled up inside other shirts. Not sure what to do? Just take a stab in the dark!

(You can click each shirt to open the full-sized image in a separate tab.)

"Inner" shirts (in alphabetical order)

"Outer" shirts (in alphabetical order)

Tangled messes

Your final answer should be a four-word phrase with a total of 15 letters.