I know you're only 21 but take your life experience and work with it. Whatever industries you've worked in, use the inside knowledge to your advantage. Invest in industries that interest you, companies whose products interest you, and it won't feel like work at all! In most sectors there's an opportunity to be right over time, for instance a lot of people say the auto industry is a tough place to make money but it also coincides with my specific knowledge, and is an area where I've made money in the past.