There has been a lot of discussion over the years whether it's best to shoot with both eyes open or just one eye open. I think the answer as to what's best probably varies from individual to individual. Some people don't know whether they shoot with one eye or two eyes open. Here is an easy way to tell.
Mount your UNLOADED shotgun and point it at some object 30 to 40 yards away. Now, assuming you are right handed, slowly raise your right thumb vertically off the stock until it blocks your right eye from seeing the front bead. If the bead TOTALLY disappeared from view, then you are a one eyed shooter. If you could still see the bead with your left eye, then you are a two eyed shooter.
Mount your UNLOADED shotgun and point it at some object 30 to 40 yards away. Now, assuming you are right handed, slowly raise your right thumb vertically off the stock until it blocks your right eye from seeing the front bead. If the bead TOTALLY disappeared from view, then you are a one eyed shooter. If you could still see the bead with your left eye, then you are a two eyed shooter.