I made a set of cheap one's that work really well in light, switching winds. Get 3 or 4 driveway markers from a hardware store. Mine were fiberglass, so I had to drill a small hole in the end to accept a roundhead brass nail. You will need some surveyor's tape. Then get some of the small plastic tool holders that end mills and such come in. You can also get them from McMaster-Carr. I cut off the solid end, and remove the cap. Put the surveyors tape over the hole and install the cap. It will stretch the tape really tight, and when you put it on top of the driveway marker, it's incredibly sensitive and it doesn't wrap around itself after 2 minutes. Their not much good in higher winds, but for something to get started with and get used to reading, they work great for not much money spent. After I put my set up, I found out the wind on the range I go to swirls like a toilet bowl being flushed and does full reversals at that.
