A: You point that end at the person or animal you want to scare or kill, and you pull that little guy right there. You don't even need to pull it more than once, or even aim. Just keep squeezing that sucker and move the gun all around.
Of course, to actually harm anything, you would need bullets, instead of blanks. I keep the bullets hidden, for obvious reasons. You won't know where the real bullets are until you calm down.
As a matter of fact, I don't want to discuss anything until you give me a chance to put some clothes on and calm down a bit myself. Your wife and I thought you would be out of town for a week. You can imagine how surprised we are to see you standing in the doorway gently sobbing, holding a machine gun full of fake bullets.
Although, from what your wife has told me, I'm not surprised to see your firing blanks.