Clean your Shotgun
Now is the time to take that gun apart and give it a good cleaning. Pay special attention to dried grease and dirt that might have accumulated in the action, which can cause malfunctions and parts breakage. Pull your choke tubes and make sure that the threads are properly clean and lightly lubricated. And just give the gun a good, general once-over to look for any worn or broken parts.
Having patterned your shotgun, you should already know which brand of shotshell and shot size your gun prefers. Now's the time to find good deals on quality shotshells. These feature hardened shot and better wad construction, and can be expected to give uniform patterns that will result in more birds in the bag.
You don't have to be able to run a 4-minute mile in order to enjoy upland bird hunting, but it sure helps if you've managed to get a little exercise in before the season opens. You'll be amazed at how much better you'll feel during a hunt if you start walking a couple of miles three to four times a week now. The same goes for your bird dog. Take him along.
Ideally, you shoot skeet or sporting clays year-round, whenever weather permits. But now is the time to get serious about scheduling regular practice sessions. Bird hunting is all about doping the angles and determining where that load of shot will intersect with the bird. No one can really tell you how much you need to lead a bird, but with practice you will work that out on your own. Busting clay birds builds confidence for your coming hunt.
Learn to Focus
We spend much of our lives looking but not really seeing. This is certainly true of bird hunters. We get in a hurry and look at the whole bird as we fumble to make the shot. On the shooting range, train yourself to focus hard on the front edge of that clay target. With live birds, focus on the eye or beak. Do this, and you will bag more game.
Break in New Gear
If you've purchased new hunting clothes, it is time to start wearing them on your regular walks. Make sure they fit properly, aren't binding in any way, and perform whatever function they were designed for. This is triply true for new boots.
You can't always get to the range and shoot as much as you would like to. This is where dry practice at home can help quite a bit. First, unload that shotgun and make sure there is no ammunition nearby. Practice foot positioning while smoothly mounting the shotgun and swinging as you move through the imaginary target and break your shot.
Most game birds are missed behind, usually because you stop your swing at the moment you break the shot. It is a common sin in the game field that we've all committed. On the range or in the field, your eyes should be focused on the target, and you should see it clearly as you swing through it and break the shot. Keep your gun moving as you trigger the shot. You'll put birds in your bag.