I am not straight, therefore I can't give good opinions on how to pick up girls, however I have talked to people who are successful at picking up girls and are straight and they say something that, doesn't make sense to me and probably won't make sense to many people on this site in particular but... apparently works.
Basically, this is for hooking up, not for full-fledge relationships. The general concept is you need to be masculine, stereotypically masculine, you need to seem manly. You can't be the good guy who talks about emotions and stuff, you can't be the guy complaining about the "friendzone" and being the shoulder to cry on and stuff, you have to be the guy who sort of "doesn't really care" about the girl, but is handsome and interesting and what-not. Basically, people often complain that douchebags always get the girl, but the truth is in these scenarios, the girl is attracted to the douchebag, so if you want the girl that's the kind of person you have to be.
You have to be handsome, working out, getting muscle, looking fit, all things that are possible and things that you can do.
You have to be masculine
You have to be impressive.
This is for normal girls, like picking up normal girls and stuff in the club and what-not, for online girls or girls in niche subcultures like the furry fandom, or brony fandom or something, being more in touch with your feelings is much more of a positive. And this won't work if you're looking for a long-lasting relationship.