How do I become a bartender?

Ok, this may seem stupid, but oh well... I want to become a bartender in a couple of months but I don't know if I can or if I fit the profile for the job. I'm only 18 years old. I want to bartend because I really need the money for college, and I think tips will get me further than an hourly wage. I know I can get the Wisconsin Bartending License for $25.00 online. The thing is, I was never Mr. Popular in HS and also I'm not someone with a smiley face on 24/7 (and that doesn't mean that I'm angry or sad) I do however have really good customer service skills and I'm very attentive and would notice if someone hasn't gotten their drinks yet. I also think I can learn a lot of bartending tricks that would help me as well. I'm also really tall and skinny and gangly looking. I don't know if their is a specific profile or if my age will hurt me, or my tall/skinnyness, etc.