This method I doubt would work in clubs, but would probably work on a crush that you got your eye on but you're too shy to approach.
I've developed this thing simple routine where you can find out if a girl likes you or not, without have any social awkwardness if she declines...
Step #1
Get her number... this is the hardest part (I think) for some people, because most guys are shy and too afraid to ask for a number. But just get it... then you can go on to the next step.
Step #2
Build Rapport... some trust, some connection... become sorta friends.
Step #3
text her (this could also be hard cuz maybe you can't afford text messages haha).
This is the dialogue you are to say (after you build rapport of course) :
you- "hey we should hang out sometime!"
"sure sounds great!"
you- "how bout saturday we see a movie?" (comedy movie, not romantic so there isn't pressure)
"sure sounds great!"
(then change the subject to something else, whatever... just get ready to end the text conversation...
*if she declined any of your before offers, then perhaps she doesn't like you... But hey... there is NO social awkwardness between you two. (if there is.. it is at its bare-minimum)
Step #4
After a day OR 2... text her again
you- "hey we still on for this saturday?"
"sure sounds great!"
you- "So will this be like a date or something?"
This is when you find out if she likes you or not...
if she says "nooooo its not a date". that means she doesnt like you, and you could easily recover by saying "oh hahaha good, cuz i was telling my friend about it and he said it sounded like a date but he wouldn't believe me when i tried to convince him otherwise".
if she says "a date? umm... idk" that means YES!!! she is interested!!! you reply "so it's a date then

".
Step #5
go on date, she likes you, now just dont fuck it up
This I call the Artemas method. I invented it. Why is this great? Because in any such event where the woman declines, the social awkwardness is at a bare-minimum, or absolutely no awkwardness at all. That's why its great
tell me what you think!
DISCLAIMER: I'm new to the forums and I don't know if someone else came up with this method, but I DID come up with this all by myself. Out of the 3 times i've used it, its worked. (1 of the 3 declined, but there was NOOOO social awkwardness).