Just do it like, simple.

Start dressing better. Grow your hair out. Change your entire personality. Everyone'll fancy you then, not a bother like. Nah just messing, they probably won't. At the end of the day, there is no one surefire way to make a person fancy you, or even be attracted to you a little bit. That being said, there is one trait that people tend to find the most attractive in another person, so if you do that, chances are you'll instantly become more fanciable. Just be funny, that's it tbh. Easy. According to multiple sources and much scientific evidence, people are generally more attracted to people who are funny or those who make them laugh. Makes sense, yeah. A study conducted in Canada saw men's attractive levels increase when they had a good sense of humour - and while women's attractive levels increased too, they didn't go up as much as their male counterparts' did. Guess lads are just clearly more shallow. Similar to this, another study saw that women are more attracted to men who are funny and creative, with further research showing that the trait of humour tends to be associated with social people with more friends, therefore making them more desirable. So there you go - if you want people to fancy you more just be funny. It'll work a lot easier if you're a straight guy, but then again, most things do.