The day before installation, dig a foundation hole 30 inches deep and 24 inches in diameter, using a post-hole digger and shovel. This will hold the painted steel anchor, which supports the pole and prevents ground moisture from wicking up and rotting the wood. For soil that doesn't drain well, add 6 inches of gravel or crushed rock before pouring the concrete. The base should be high enough that the pole can swing up and down with ease. Shovel in 6 inches of concrete, let it set for a few minutes, and drop in the anchor. Check the anchor's alignment using an 18-inch bubble level, then fill the hole with concrete and trowel it smooth.