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For this birdbath, you will need four long, straight, and relatively thick branches. Consider taking some off a tree, that way they will be relatively fresh, without any rot. The branches should be about 2 feet (.6 m) long, so that they are large enough to be staked in the ground and still elevate the bowl a few inches from the ground. The branches should also be at least 2 inches (5 cm) wide to be sturdy enough to support a bowl. The branches should be in a square pattern, equidistant from each other. Push them into the ground, approximately a foot, so that they are securely staked into the dirt. You might want to dig up the dirt a little, to help place them underground, and then fill the holes in around the stakes. To get the distance right, try balancing the bowl on the stakes ahead of time. See how far they need to be from each other to obtain optimal balance. When, you have found a good placement, mark the ground and begin hammering your branches in at that location. Place the bowl on top of the four stakes. Check to see if it well-balanced between the four branches. Any bowl will work, but it is best to use one that isn’t valuable and won’t break. A wooden bowl is an excellent choice. It will generally be easier to balance a deep bowl on top of the stakes, but do not fill these bowls up all the way. 1-2 (2-5 cm) inches of water is ideal for a bird bath.

Summary:
Find four sturdy branches. Hammer the branches into the ground. Place a bowl on top of the stakes. Fill the bowl up with water.