The Family Handyman DIY Tip of the Day: Deck building tip. When you’re building a deck or other structure solo, it’s pretty hard to level long joists and beams, then hold them in place while you secure them. Here’s one way to do it. Secure one end of the joist or beam, then support it with a car scissors jack. Crank the jack up or down to level as necessary, then secure or support the other end at just the right position.