Former teenager here...
Want the kid to keep their room cleaner? Ignore it. Pretend that room doesn't exist...
Dirty clothes not put down to wash? Let them run out of clothes. Not your problem...
Another former "good" teenager here, and yes to the above.
Don't be afraid to pass off responsibility to them, too. My mom was sick of me wearing something once for a few hours, not dirtying it up all, and tossing it in the wash. So, at 12, she showed me how to use the washing machine and dryer. Mom had first dibs on times she got to use the washer (generally Saturday and Sunday mornings when I was sleeping), but it was up to me to do my own wash. There were times I ran out of clean clothes. There were times my hamper was bursting. But hey, life lessons at a young age. (If I asked for help, because I had tests and essays or wacky plans, mom would help out. But I did her laundry too sometimes, so it was more of a "we help because we're family," not "you do the laundry cuz you're mom.")
Same with food and dinner. I was a bit of a picky eater as a kid (no meat other than chicken or steak, my food couldn't touch each other, etc.). Since it wasn't extreme (and there were no food allergies), my mom would get me involved with the meal planning for the week - basically, she's planning on cooking x, y, and z this week, and what did I think? If I ever pushed back (which was rare), her response would be, well, I really like this dish, and we already had your favorite, so you can make your own that night if you want. There were a few times that I made my own dinners, but it was rare, and I usually regretted it.
I'm really fascinated by allowances, because I never got one as a kid. I was expected to do chores because I lived there. My parents gave me money when I would go out and do things... while they weren't mustachian by any means, they raised me to not want much and to be frugal (the amount of times young teenage me convinced my friends to go out for ice cream instead of full meals, or to just split fries or something...). When I was old enough to have a summer job, that changed. They specifically didn't want me working through the school year so I could concentrate on school and extracurriculars, but I would be routinely asked 'you okay on money?' (To be fair, as a 27 year old homeowner with a good full time job, I'm still routinely asked 'are you okay on money?')
My parents always (usually) treated me like an adult, even when I was a tiny child. They respected me, let me make my own choices, let me fail at things (mom had to reign dad in on that one). I'm not sure how, but my mom specifically managed to find that really good balance of friend and parent/authority figure.