Use Facebook as an add on to your sarging, not as your main source for getting numbers. Keep flirting and messages to a minimum. I mean, use them sparingly.
I deleted my Facebook, and am now doing much better female wise. I am dating someone at the moment, though, so I don't socialize with other women as much ad I use to.
I'm not knocking the use of Facebook. I just felt for me, that it wasn't necessary. I've been without it for 4 months and don't miss it a bit.
Learn to sarge without it first before you dive into adding Facebook to your arsenal.