Learn how to run your OWN boat, not someone else's, especially calling the shots as skipper. And above all,don't get slotted into specialty crewing. If you jump right into big boat racing that will probably happen. Simply tailing a winch does not equal knowing how to sail.
The best sailors come from dinghy racing and are far more versatile than people who learn only on big keel boats, . The more you do on a dinghy by yourself the more you will learn. It ALL scales up to any size boat you eventually end up sailing.
^ this ^
I would go a step further and say that it's impossible to learn to sail -well- on a big boat. It's possible to learn to do a job-on-a-sailboat (such as trimming, helming, etc) very well but putting the whole package together can only be done on small boats. There are a bunch of reasons for this, one is that small boats are generally more responsive & give feedback on when you're doing something right or wrong; they can do the same thing many times in an afternoon, the effect of weight & balance is easy to study when your body weight has such a noticable effect; and so forth.
Then it's also true that some things you don't learn at all on small boats. Navigating for one!
Do a recognised training course. You will learn more in two days than you will in months of rail meating with a bunch of well meaning racing sailors. With about 4-5 days training you will be comptent in the 'mechanics' of sailing , and then you will be useful on a race boat. Don't let the tits thing worry you. any boat that still has issues with female crew these days you wouldn't want to sail on anyway. Good luck with your sailing.
Oh and whilst on the subject of tits.........
I think you were the last person who brought them up, yes?
Taking a course is an excellent way to get a look at all the various tasks of sailing and how they relate to each other; something you're not likely to get from sailing with friends or crewing on a race boat. But it's still a good idea to get a reference or two from that specific course & instructor because quality varies tremendously.