An overly harsh sense of humor or rude behavior is a major turn off. I know I'm sensitive and it would eventually become a problem. A major red flag for me is someone who speaks ill of every single one of their exes. Usually means they aren't owning up to their share of what caused the breakup. I agree on poor hygiene as well. And partying. I'm out of the stage of my life, and while I don't judge others for what they do, I just don't want a partner who still rages every weekend.
Turn ons are kindness, very good manners and etiquette, a silly sense of humor (I absolutely love to laugh), a laid back attitude, book smarts, goals, interests that are actually explored and not just talked about. I love strange personalities as well, and introverts who can socialize a bit. Oh and sexual confidence, or at least a curiosity in learning new things.