If the waitress asks for the check just tell her to split... the girl will never ask why u split...
If u get the drinks directly u can buy the first round... make her buy the second... seriously, if u get the first round and the girl is not offering another one I usually don't want to hang with them any more anyways. So if she's not mentioning it by her own - just ask, so u are getting the next round? If she's not, grab ur stuff, stand up and walk out. Well, don't forget to wish a good night
I usually don't care buying the drinks when I'm on a meet up with a girl... I think that's part of being a man and I never had a problem with the bounce back by spending 10 bucks on the first drink of the night.
In a club... well here I never buy girls a drink! No matter what... if a girl asks, I tell them exactly what noochie mentioned before.
Real story: We have been to a club in Chicago with Bottleservice and the waitress came over and told me she needs a drink... I told her that should be easy for her, cause she is the waitress... she replied that she always gets drinks by some guys.
I told her my 'no drinks for girls rule' and she was kinda pissed but still was hanging around and talked about her getting drinks and then talking about her boyfriend and bla.
I made up a little game and made her deserve the drink later (after she was really suffering for one

) well I didn't recognize anything from her boyfriend later that night if u know what I mean
It's always a point of presentation... u can also say something rude as long as u come along funny and cocky. Girls will just punch u and think it was a joke till u proof it wasn't. Hehe.
Hope this helps,
cheers