Don't wear baggy shirts or pants or clothes in general.
Wear something fitted not too fitted but not baggy either. Nothing grinds my gears more when a guy is wearing a button up built for a fit guy that's bigger and the shirt is big as fuck tucked into his pants like a tent. I'm just like NOOOOOO THE HORRROOOR! get something fitted. Like a slip fit or extra fitted shirt or something depending on how skinny you are. Same with pants too. Don't buy a classic fit built for muscular legs get something slimmer like I don't know what it's called exactly but my bf is like a twig and he's small so I bought him these jeans at express called Roccos they are built for a skinny guy fitted but not too fitted still a boot cut or a straight leg but not too big not to small just about right. Hope that helps :)