Unless your gh is very small, you'll need help unrolling the plastic and hoisting it over the gh frame. Before you cover the structure, make sure to cover any screws that may tear the plastic with duct tape. My daughter helped me unroll the plastic, but we could have used another pair of hands also. You can sort of eyeball the middle of the plastic by the folds. Make sure to leave enough plastic on both sides of the structure. Since mine was along the fenceline, I was able to secure the plastic to the fence by screwing the pvc pipe to the fence with the plastic between.
Depending on where you locate your gh, the wind may be a factor. We use batten tape to keep the structure from flying into the neighbors' yard. You can attach it the ground with tent anchors, or if it's against a fence drill one side into the fence and anchor the other to the ground. We secure it diagonally. To secure the bottom of the gh, you can run a board along the bottom and staple the plastic to it, or you may just use bricks or rocks. We'd done both. The only problem with using a board is you can't easily raise the side when it's a warm day. Use some spring clips to secure the plastic to the pvc pipe, depending on how long or large your gh is. It will help when the fronts blow thru!