here are lots of ideas since you don't specify what kind of lamp/light https://www.youtube.com/results?search_query=diy+PVC++lights
Here's a tutorial on Hometalk:
Missy here are a few ideas. If you type " PVC lights" in the search box you can find many more. I have chosen 3 for you to view. Hope this helps.
Here is one idea: https://www.hometalk.com/26161295/pvc-pipe-lights
I used pvc for the neck of these lights but I used an inexpensive light for the shade part. https://michellejdesigns.com/sconces/