It's not too soon to start practicing with your turkey calls for the upcoming season. You don't have to be an absolute master of the call to be a successful turkey hunter, but being competent sure doesn't hurt your chances for success.
Start out with your old favorite calls to get back in the groove. You might want to replace some of your diaphragm or tube calls because latex deteriorates with age. Better to break in a new call early on than have last season's favorite go sour on you in mid-season. Also by starting early you can experiment with new calls (both makes and call types) and maybe find something that works better for you.
With all the excellent video and audio tapes available, good turkey call instruction is widely available and learning effective techniques is not the slow curve it once was. Visiting local turkey calling contests is also a good idea. Hearing top-ranked competition callers and attending their seminars might help your technique.

Even with deer seasons winding down, much other hunting is still available. In particular, waterfowling at the southern ends of the migration routes is at its very peak in the mid-winter months.
Whether you are after ducks or geese, cover the basics with good camouflage, good waterfowling guns, non-toxic loads and effective calling. Newly arrived birds are somewhat easier to work but remember, these birds are at the end of a migration that took them over lots of blinds and decoy spreads and they've been exposed to lots of calling.
Cut back on the standard hail and comeback calls. Use them enough to get passing birds' attention but go sooner to confidence calls and be subtle. Particularly in flooded timber and swamp shooting, loud calling is not necessary.
The use of a trained retriever is highly recommended. Waterfowl are very tough and tenacious of life. Even hard-hit ducks will often dive or swim into areas where they are difficult for the wading hunter to find or retrieve.

Staying warm is about both keeping warmth in and the cold out. Your body generates its own heat and that's what properly insulated clothing retains. However, the body also generates moisture and that has to go if you want to stay warm. No matter how much you bundle up, if your underclothing absorbs and holds moisture, you will soon get clammy and cold.
"Breathable" insulation traps heat but wicks bodily moisture out and away from your skin. Windproof garments also allow you to get away with less insulation. For next-to-the skin comfort, silk is the traditional favorite. However the new generation of synthetic fabrics rival the classic silk and wool combination for both wicking and insulation ability.
Goose down is premium insulation. It wicks, it breathes and it is wonderfully warm. However, if it gets wet, it loses all its good qualities until it can be dried. If you are wearing down garments for insulation, make sure that you have some windproof and waterproof outerwear available.

Perhaps the most useful thing we can learn from post-season deer scouting is where the deer, and particularly the bucks, end up. If, all season long, you played catch-up (and not too well) on local deer movement and habitat and cover transitions, taking a look right after the season can put you ahead of the game next season.

Don't wait. Get out right after the season is over and take a look. Once the hunting pressure slacks off and certainly by the time spring "green up" occurs, deer will begin to develop different habit patterns and travel paths to accommodate new environmental conditions.

You want to know just where they all went as the season ended. Look for well-used winter trails and other active sign. Try to discover late-season food plants and feeding patterns. Look for late-season buck sanctuaries, which will likely be different from buck hangouts in the early and middle part of the season. By knowing where they went, you can get there first next year.

Perhaps you think it's hard to miss a gobbler's head with a wide shotgun pattern. While filming the "All Stars of Spring" turkey hunting video series, we saw plenty of misses.
Modern specialized "turkey" chokes don't throw a very wide pattern at short range. Under 20 yards, we've seen patterns as narrow as eight inches. That's more like a big bullet than a pattern. Unless your turkey gun shoots precisely dead on, an up-close gobbler can easily be missed.
In the old days, correcting a shotgun's point of impact was fairly difficult, involving bending the barrel and either bending or altering stocks. Today adjustable rear sights, both open and optical, and good mounting systems are available for shotguns. With these, it is as simple to correct a turkey gun that's shooting "off" as to sight in a rifle.
With a well-sighted gobbler gun, you are ready to take on turkeys at all reasonable ranges rather than be put at a disadvantage by tight patterns at close range.