I screwed together about 5 pieces of scrap wood, 1 x 2's and 1 x 3's, starting with two 1 X 3's about 8 - 10inches long at a right angle for stability, then a 1 x 2 about 12 - 14 inches across the legs. I attached a couple 6 inch pieces randomly. The chicks play on it like a jungle gym.
I put my 4 chicks out on the lawn in the "play pen," which is a bottomless dog crate, for about 30 minutes to an hour morning and night. I love watching them find something, usually inedible like a dead leaf or twig, and chase each other like Tweens who have found Justin Bieber's phone number. I can't help laughing when they do a tug o' war, and then one gets the prize and runs around the pen like a crazy chick.