There are a wide variety of courses, that can help you develop sailing skills as well as the other skills that are so important to have on a boat. If I were in your shoes, and I had the money to do this, I would probably would take focused courses aimed at developing well rounded skills. I would probably take a J-World sailing course which will focus on sail trim and boat handling. I would probably sign up for a good first aide course at a local community college, and I would sign up for an in depth Navigation course either at a captain''s licence prep school or through the Power Squadron. I would also go through the Power Squadron''s intro to boating which covers safety and rules of the road as well as a wide group of helpful topics. (At least it did the last time that I knew anything about it which is a long time ago.) Good physical conditioning is important as well. This is not about ''being attractive''. It about being strong enough to pitch in or even take care of yourself when things get dicey. If you live in an area where there is sailboat racing, it should be pretty easy to get aboard a race boat as crew. Racing is probably the fastest way to learn sail trim, and how to effectively use winds and current. If you can approach a boat needing crew with those skills you are more likely to be invited aboard.
Where are you located?