Starting a tiny (tiny) business for a teen to earn extra money - tips?

[justagirl]

So basically, I've recently been really interested in doing cute nail designs, and everyone always comments on my nails saying how good they are. I never really thought about doing them on other people, but my mum suggested it today and it got me thinking. I am 15 years old and this would only be a very small thing outside of school, but if I were to charge people £10 (is that a reasonable price?) for their nails it would be nice to have the extra money to save for university in a couple of years. I was just wondering how I would go about getting clients and when/where I would do them + juggling schoolwork, if each design takes 45 minutes to an hour.
So I'm just grateful for any tips at all you have, & if this is a good or silly idea!! I wouldn't be able to do them during school lunch hours because my school forbids nail polish :-(.
Also, do you have any name suggestions that I could use on facebook/twitter?

P.S Heres an example, tell me what you think!
http://instagram.com/p/QHc43OF2y7/?fb_so...er_message