Let it sit at room temp and carb like primed bottles? I plan on taking this to a party 3 weeks form now so I have some time.
And after it sits, blow out some of the yeast at the bottom, then rack to a new keg before you move it to chill. Unless you don't mind if it's a bit cloudy.
It might be a good idea to hit it with a few PSI just to make sure the lid seals properly