For a couple years Keith Foster and I have been using contractor's laser levels to line up our wind flags @ EG.   it works real slick though you have to get there the evening before the match---they don't show up well during the daylight.  I set mine on my bench rest and put the red dot in the middle of the backer---then I walk out carrying my wind flags.  if I am in line properly my body blocks the laser from the backer and I simply reach out and set my flags an arms length to the left of the laser beam at the proper distances.  since doing it this way I can set my flag in one walk out and a very seldom have to make any adjustment the next morning

just as a heads up---I was in my local Rural King farm supply store Monday and they had a whole bunch of pretty nice ones on sale for under 15$ in their clearance item aisle.  I picked one up. Its a Bushnell Pivot-point and it purports to have a stronger brighter laser cell.  
 My old one works fine but you have to set it on a tripod or clamp it to the bench rest.   the one I just got comes with a little windage and height adjustable base that'll set nice and solidly on the bench have found yourself walking back and forth adjusting your windflag alignment you might want to pick one up and give it a try.

Ben, 'cause its usually windy at Etna Green and Keith blocks the wind pretty good

I'm not that good a shot and I need all the legal help I can get.  I usually put out out 3 wind flags at about 50/100/150 yards I have a wind probe velocity indicator I set out at 25.This seems to be a fairly standard set upt there thoug some guys use a few more flags and positioning will vary form shooter to shooter.  I align them up so that I can see them with my left eye while looking through the scope with my right.  I try to adjust them for height so that all of them are visible with the farthest one on top.

when I'm shooting 22rf. I also put a small streamer on the backer frame above the backer as well.  at EG the berm is quite close behind the backers and under some conditions we can get some real squirrely winds coming over the berm even if the other flags show steady conditions.

Wind indicators vary widely and wildly.  some are store bought rigs form sincalir of champion shooters supply and other vendors but most are home-made.  Pinwheels, weather vanes, streamers, and  "elephant condoms"  and all sorts of combinations and variations are all to be seen.  

I've cone to the conclusion that all of us in this game are obsessive/compulsive tinkers and our wind indicators give us some welcome relief from messing with guns, loads, moulds, lubes, iron sights and optics, bench setups and reloading tools.   Anyway the more "stuff" the better excuses we have---r-i-i-i-i-i-ght?