How do I install Ameristep tree steps?

I just bought 4 of these to raise a stand that I would like to raise another 3-4 feet. I have 4 3 foot ladder sectionals that I plan to raise to get me up the tree after using these 4 steps for the first 4-5 feet of the tree. What is the boards experience in installing these and what is the correct way? I have seen some that install them one on each side of the tree and others who install them in a line up one side of the tree.