I initially got into air guns for yard pest control too, still is a big part of my AG shooting. Sight your rifle in for the common average range you shoot at. I have most of my rifles sighted in at about 30 yards zero. As far as a steady hold, the same basics apply to AG as powder burners. I always try for some kind of improvised rest if I can get it. A lot of my pest bird shots are taken from a sitting position, elbows on my knees. I've been pretty successful with shots from sitting on my butt. If I have to take a standing shot, I try to get some kind of rest to lean against, a wall of the house, a tree, etc.