How do I make myself subtly beautiful?

I like a guy, and since I got this haircut I think he's been checking me out. Look, I know I'm young (12) but I want to try and make myself subtly beautiful. I already use concealer because I have dark rings under my eyes, and I have a shiny nose and so I powder it. Finally, I have some plusses: I have high cheek bones and very long legs. I am also skinny and have a nice figure (except for my bony xD) and well... I have some pimples and i have a long face that I hate. I want to enhance my looks, I think I'm ugly and I need the fastest and easiest ways to fix the things I listed and to enhance the things that are good. And also, how can I become approchable to him? And if you know how to make a school uniform look different. I just have to wear a polo and a pair of black or navy shorts. I really like him so I wanna be you know... :3 Thanks in advance ;)