May 15th, BWCA, 10 days, 8 campsites, rainy, 50°F cool, comfortable.
This is a homebrew 10×12 silnylon tarp.

We search out dead, dry, slim poles about 5' long from the surrounding woods. We have never had to cut anything. If you look, they are there.
We stake down two corners (parallel to the ridge seam) to take advantage of trees to be used for the 'pull-outs' located the ridge seam, edges, and middle.
Then we run lines from the ends of the ridge seam to outlying trees, creating a back wall with about a 80° slope.
Next we run line from a corner pull-out, to a pole, then to stakes, trees, or rocks, to create the roof pitch.
Last, we fine-tune to create volume and taughtness, using whatever pullouts are in the right place. The wrinkles on the back wall indicate where the ridge is pulled up and out to the tree behind. You need to have a consistently sloping roof to avoid collecting a 5 gallon puddle. And if you can get it to slope towards the back wall or to one side you won't create a mud puddle in the front.
We are frequently able to do this without front poles by running lines to convenient trees. This is were imagination and experience can really reduce setup time.
This pitch is fairly open as we are well sheltered by the woods. If necessary, a very low and tight pitch can be accomplished by angling the poles.