So, about 80 percent of clothes I own are graphic tees, tank tops, skater hoodies, cargo pants, etc. I still wear most of it, I'm 19 going on 20. I noticed it looks quite out of place now, especially when I go out with my brother and his friends, who are upper 20's, all dressed in nicer clothes, jeans, henleys, button down shirts, more adult things.
So I don't need to get rid of all of it, I understand. But the urge exists for my wardrobe to grow up now. Trouble is, not sure how I would afford too many new clothes right now, I don't want to just throw away things. Even donating stuff will cause me to be out of clothes eventually. I would just keep the few jeans and the couple button down shirts, but the 20 or so graphic tees and "skater" clothes I feel silly wearing now. Where can I get a bit of money for these things?
A consignment shop. But you won't get much. OTOH, you might get cheap clothes at a consignment shop, whether you sell your old tees or not. Believe it or not, you can find decent clothes there, though it's tougher than at the mall.
donate at GoodWill then go around front and buy from GoodWill.
Same at St Vincent DePaul
Seriously, this isn't sarcasm:
Find the local online "mom groups" on Facebook or Craigslist or Kijiji or Reddit and post up an ad for your t-shirts there, either as lot or as a X$/shirt sort of things. Some mom out there will be happy to buy a bunch of skater t-shirts for her kid at a discounted rate. Stick the mom groups because general buy and sell groups are flakey; you'll get a bunch of lowball offers and the ones who promise to buy will flake out at the last minute, probably without giving you any notice. The mom groups are serious business though. No fucking around. You'll probably get competing offers.