US citizen needs UK visa?

Greetings! I am 20 year old U.S. citizen and I would like to go to the U.K. just to work. I looked at all the tiers and even though I can go the student route I don't want too because you can only work 20 hours a week and for the work visa i've been reading that I need a sponsor before I even get there.Finding an American company that will transfer me is not likely because I don't have a career yet/I cant apply for a highly skilled worker. Is it possible for me just to go to the U.K. and find work without the visa? what are my options???