I know how you feel, I've felt similar before. What features do you feel are ugly? It's mainly confidence, you need to boost yours and when you feel prettier you normally look it.
Find a few features you really like about yourself, and maybe a radical change with those you don't like an adventurous haircut or colour, or some kind of piercing, or a new style of clothes. Anything to make yourself feel better.
Make-up can make a huge difference sometimes, just to even out your skin tone or add some colour and fake tan can give you a positive self-image if you want to try it, although I'm not personally a fan. (I don't mean going orange like some people but just to give yourself some colour and look healthier).