What are three things that a skinny guy should never wear. And if you want to be really helpful... add 3 things that skinny guys can pull off really well :)
Most Helpful Girl
I really can only come up with skinny jeans. Skinny jeans make anyone's legs look skinny. I know a lot of skinny guys and (being a girl) seeing how much skinnier they are than me sort of bothers me.
I think any guy can pull off khakis. I think that they usually hide how skinny someone may be. Same goes for sweatpants and casual dress shirts or plaid flannel.
Most Helpful Guy
Don't wear baggy clothes hoping it makes you look bigger.
Do wear clothes that fit.
If your clothes are the right size for your body, it makes your body seem the right size. When the clothes fit badly, it looks like YOU are the wrong size.