I use cable ties to attach the shade cloth and fabric to the PVC. I have the shade cloth pieces attached together and leave them that way, then I wrap them around the PVC and run a cable tie through them. 6" cable ties poke through the weave with no problem. I use just enough to keep it taught - every 6 inches or so on the end ribs, then at the bottoms on the middle supports, and anyplace where there's gapping or sagging.
To attach the fabric, I cut small slits in it and tie it to the PVC with more cable ties. It goes a good bit closer to the ground, and it's what keeps the sun out in the morning and evening.