3KillerBs already linked the main thread that we like to use for examples, but some additional notes: you can pretty much use anything that's chicken safe for clutter (so yard junk is ideal) but just as important is the placement of clutter. The best placement of clutter will allow a chicken to walk around it, jump up on it, go under it, etc. To prevent chicks from being cornered, any obstacles against a wall should have extra openings cut out to give chicks an extra escape route.
