Not as part of his normal attire but there must be times when he was drawn wearing a cap.
it might fell off.
Cap du surhomme
yes......
Yes. He does. And his sperm DO have their own capes, and like Superman, they too wear their undies on the outside.
A invisibility cap
cap
Superman does not wear headgear. You may be thinking of the Science Police in Adventure C9omics who wear unusual angular helmets, vaguely like Japanese troopers with some modifications. the helmets are Navy Blue, and have a solar-type badge in the center, otherwise a bit Oriental.
Cap du surhomme
yes......
Superman wears Chuck Norris pajamas. He wears Jack Bauer pajamas!
Wear a shower cap, or, wear a swim cap, your choice!
Underpants
Yes. He does. And his sperm DO have their own capes, and like Superman, they too wear their undies on the outside.
Yes you can wear a skull cap under a ski helmet.
Shower Cap Night Cap Swim Cap
orange cap
A invisibility cap
Unusually, superman has no mask to wear when he is saving people. So in order to save his secret identity, he needs to dress up like a normal person.