Make sure you use the harness on the way up and down the tree too. In addition to the haul lines, make sure you tie the bottom half of the climber to the top half. Nothing like sitting 20' up a tree and have your stand section fall to the ground. Fortunately this has not happened to me.
Other than climbing up and down safely, they are about like any other treestand. Dress warm, don't move much and wait.