This one feels a little self-explanatory and most of the people I know Hip or Un-Hip know what I'm getting at when I say this. Especially when I've already got that look in my eye that means I'm trying to get into it tonight. It just means getting drunk. But be careful, it makes people uncomfortable (most of the time).
"I'm trying to get wet tonight, man" or "Phew, I'm feeling pretty lubricated right now"
Use this phrase at your own risk. The last time I said it all the females left the room to get their friends to help them spit on me.