you could tie it. just bunch the back up into a tail and put a ponytail fastener around it.
tuck it in
Easy get it kinda big and tuck it in ur pants pull.it out some so it is airy akd light than take a nice belt and wrapit in the middle
You can belt it and wear it with tights. OR you could roll it and tuck it to fit you.
rip the front a lil bit and tie up the part around your waist.
Pull the extra fabric in the bottom and tie it with a hair tie, then you can party like it's 1996! :D
Or you could buy a girl's shirt, if you have a way to get to a store. It's almost winter, right? That gives you a reason to carry around a jacket to hide clothes inside, after you buy them. It would keep them out of view of parents and such.
And trust me, no random shopper is going to give you a weird look for buying a girl's shirt. There are dozens of other reasons why you might be buying it, other than to wear it yourself.
unless it's a small shirt..you can't. the only thing you can do is it accentuate the girl within that shirt.
maybe shrink it in the dryer?
Tie the bottom part of it up if it's a button up.