I got the area first sealed off with a tarp, then I put mylar up. I still need to make the mylar door with velcro so it is lightproof, but I'm close. I am wondering if I should try a small aeroponic system to go in there. I could have a 10 gallon rubbermaid tub in there and have the resovior outside the chamber.

The left photo is pre-mylar, and the right photo is it mylared up. It isn't as bumpy as the picture looks.