Clothes

to change clothes means putting on new clothes.
Example: I need to go home and change clothes before we go out tonight.
She spilled coffee on her skirt, and she went home to change it.

to change into clothes means putting on different clothes.
Example: It's getting hot, so I'm going to change into shorts and a t-shirt.
Give me a moment, and I'll change into something more comfortable.

to exchange something (for something else) means you took it back to the store and got a new one.
Example: My pants were too small, so I exchanged them for bigger ones.
The outfit was a little old-fashioned, so I exchanged it for something more modern.

to try something on means you wear the clothing before buying it to see how it looks.
Example: Can I try this on? Yes, you can try it on in the dressing room.
This shirt looked better when I tried it on in the store.
When I tried the shoes on, they felt uncomfortable.

to fit means the clothing is the right size for you.
Example: This dress fits me perfectly.
These pants don't fit me. They're a little too loose.
This shirt fits me, but I'm not sure if it's my style.

to suit someone means the clothing is their style and looks good on them. You can also say, "It's your style."
Example: That outfit really suits you. It makes you look thinner.
That blouse really suits you. It's just your color.

to go window shopping is looking at clothing without the intention buying any. Note: do not say, "eye shopping"
Example: I like to go window shopping to see what's in style.
I go shopping every weekend. And if I don't have money, I will just window shop.