Hmmmm...I don't know really, because Im probably not attractive enough to give advice!
I do tend to ignore what everyone else is wearing though and wear things that I think are nice, and suit me ok...helps when I'm in a thin phase, otherwise I do struggle as what I like doesn't like me!
I wear minimal makeup but just enough to make me look more alive than dead
I don't worry too much about holes in things (maybe tights) or paint and stuff on them, it's just part of life (I paint a fair bit, walls etc as well as pictures, and DP is a professional decorator). I am fairly scruffy in normal terms I think. But people tend to say I look nice anyway.
Hair is very important imo because I know when my hair feels rubbish, nothing else works. So I make time to wash it, which always helps enormously, or tie it up at the back if there's no time.
I think it's all about finding a style that feels genuinely like you, and sticking with it because it just works out that way most of the time anyway....so I know my hair is better long, and looks ok bunged into a clip at the back. And practically speaking it happens most days anyway.
Same with jeans, they work, they look ok on me, they are what I end up in all the time.
Other stuff - tops etc just sort of vary depending on weather/day/mood etc.
If you figure out what makes YOU feel good inside as well as about your appearance then it's not so hard to keep doing it. For instance I feel uncomfortable in dresses, so I don't even try any more with those, and trying to make my hair straight/keep it in a short style that needed lots of upkeep/dyeing it a trendy colour etc would not work for me. Find what works for you and go for it.
Good luck x