Encourage partygoers to imagine they're far up in the air as they navigate this narrow beam. An umbrella adds an authentic aerialist touch and may help with balance (just be sure to keep others at a safe distance to prevent umbrella- spoke pokes). For extra fun, place a dime on the far end, which the high-wire walker may keep if she retrieves it and returns to the starting point without tumbling off. You will need: Two-by-four stud (ours is 8 feet long, but you can adjust the...