I would personally leave it in the primary for about a month then rack it to secondary and let it age for 6 months or longer. This is what I'm doing with the barleywine I recently brewed.
A piece of foil over the top? I have the cap, I don't have the piece inside there but I can't find the tubing I was going to use for a blowoff so I'm kind of screwed on that option so any other ideas would be helpful.