Equally important, decoys enable you to control the birds, making them land in front of your blind for a good, close shot. Regardless of what species you're after, leave an opening 10 to 15 yards wide where you want the ducks to land. If you don't, they'll light outside your decoys, beyond gun range. Remember, too, that ducks will always make their final approach to the landing zone from downwind. Place your decoys so as to set ducks down in front of the blind, or to draw them past it.
Puddle ducks dislike flying low over other puddle ducks on the water.
In a crosswind, it's difficult to rig the Double-O without making ducks fly over one of the two groups of decoys. Set the decoys in a loose crescent with the opening facing downwind. Some hunters use up to 20 dozen decoys, although 5 or 6 dozen is more common. When hunting a fairly open shoreline, place a few decoys on the bank as well. If you set up in a cove of a lake, try running a leg of your spread out into the big water where passing ducks will notice it.