Fashion First Aid! Serious help needed! I’m dying to know the answer?

[Charlene?Lewis]

Well, I'm aware that I've posted this question before.
So, my school has been allowing hipster skirts for a long time. When I entered the school, I got my uniform too large, so I can make my skirt hipster. But the shirt is too large too, so I look fat (actually I’m not that fat). Now I’m a sophomore, so I ask my mom to go to the tailor and make my uniform smaller, but she only brings the skirt (with the size that I loved) to the tailor but I REALLY DON’T NEED IT! All I need is some shirts with smaller size, but my mom said “It’s still in a good condition, besides we cannot make a shirt smaller even in a tailor, so I won’t bought you new ones.” Now the skirt is already reduced in size, but it’s hell too small that I can’t do it hipster! IT DOESN’T EVEN LOOK GOOD AND IT’S HELL NOT COMFORTABLE!
Now that I have shirts too big and skirts too small, (I def can’t bring it back to the tailor, school’s in 2 days) what can I do to make my looks better? And I mean skirts more hipster and shirts smaller. Thank you!