3- Don't fear rejection
What do you have to lose by being turned down? A little pride, and after it happens a few times (because nobody bats 1,000), not even that. Suck it up. If you go into a pickup fearing rejection, that's what you'll project, and that's what you'll get. Be less attached to the result. Imagine that you're just approaching this woman to have a conversation, not to bang her. If it goes further than conversation, consider it a bonus. A warm smile and a few quick jokes will show your best side, and warm her up to you that much quicker.
But remember: If a woman is considering you as a sexual partner — which is what you want — what you say is probably not as important as how you say it, including tone of voice and, of course, body language. Project confidence by looking into her eyes and standing or sitting upright, with your shoulders back rather than hunched. Don't let your voice go up an octave, which is common to all people when they're nervous. Make your gestures slow and deliberate, like James Bond, not fast and fidgety like Pee Wee Herman. Bear in mind that confidence deters rejection.