We started by collecting a whole lot of milk jugs! We ended up using seven jugs for a 3'x4' window. Make sure they are washed well!
We decided on a design that we liked - alternating small and large rectangles. Then we made two patterns and traced them on the smooth parts of the milk jugs. You don't want the textured parts, like on the handle and the bottom. You can trace your patterns around the corners. They flatten out well once they are cut.
We cut the pieces out using scissors. Then we sanded each piece with medium grit sand paper in a circular motion until they were textured and no longer shiny.
Next we laid the curtain out. We made holes in each piece using a nail that we heated with a candle. A tiny hole punch would work well.
Then we used some key chain rings (we had a whole bag of them for some reason) to hang our curtain.