ok but seriously, i've been to my fair share of house parties
as the host, hide all your expensive stuff. not because people will steal, but because they might break it. vases, plates, etc. hide that stuff.
have a table for beer pong. start a few games of anything, really. beer pong, slap cup, flip cup, never have I ever, truth or dare, spin the bottle. start those games if it gets boring.
as the host, try not to get super out of your mind drunk, in case stuff goes bad. you'll need to have some sort of intelligence.