Drill small holes through a length of plastic tubing that is the correct size for the pump. Then cut pvc pipe into 5-8 inch segments, punch small holes through their centers, and thread the plastic tubing through the holes. These will be staked in the earth and provide a stable base for the tubing. One may want to put a point on the bottom of the small pvc pipes so they are easier to stake. There are many other ways to build the sprinkler system, so check out your local hardware store for some inspiration.