I dont think BL really is supposed to allow these sort of questions, maybe I'm drug culture?
But avoid depressants like alcohol and benzos as this can be very dangerous. If you must drink, sip a beer or 2 over the evening. GHB/GBLs affects are powerful enough really.
Stimulants go great with G as they take away some of the drowsiness, allowing you to take doses that would have you euphoric but on your arse, but feeling more energetic, allowing you to dance/fuck/whatever.
Get a feeling for G first though. Never take as much G as would ordinarily knock you out without stimulants, as you may get caught by surprise and take too much.
I've only done GBL, and it took me a few tries and a few naps having knocked myself out before finding my perfect dose and learning how to use it properly.