How to get big?

I have a detailing business that I do after school. Its mostly my freinds and there parantes cars that I detail. I have one of my freinds working with me and he gets paid well and I make good money doing it but I want to grow and have to work every day and not this shity maby once a week deal. So whats the best way to get more business. I do a good job and Iam really cheap compared to other people. Iam mobile but I have to have water and electric everything eles I have coverd. I was thinking about geting a sticker made for my truck but it be a tastefull one. So what are some other ideas for geting my small rinkey dink company to get big? Help a guy out.