I've been a member on the refuge for liek a year or two I think? but never have they activated my user id.
additionally, that place is full of drama. it seems like every other thread turns into a you know what match.
Don't you be dissin us Fugers

Ever since they restricted user activations it's a core group of guys on the forums and a lot of BS is flung between everyone, most in jest.
As for the Op's questions...
Your turkey gun will work just fine. Make sure to use steel and not to use a full choke. Modified or improved cylinder work well.
As for clothing, your turkey camo will work. Movement is more of a factor than concealment imo. I've shot ducks sitting on a rock in plain visibility by just holding still while they worked. Waders are a must. I recommend getting a pair that breath. I've ran insulated ones and they are a PITA unless you strictly hunt cold weather. During the early season or during pack ins they make you way too hot, you sweat, then you still freeze once you sit down. Layer up and get some breathables. You'll be able to strip warmth layers according to hunting conditions.
Second the craigslist for decoys. A dozen is a good starting point and may be all you need depending on the birds you hunt and location. For pack ins I use 6-18 and on the river I use up to 6 doz.
A dog is key imo. It saves the hassle of having to hop in the boat and pick birds up every time you shoot one. Also if you're around tulies you will inevitably drop a bird in the thickest part and I'd rather have a good retriever spend 3 minutes finding it than busting the brush for 15 trying to find it. They have a nose to locate em, we dont. Dogs arent necessary, but I wont hunt without mine.
For calls a cheap double reed is a good start. Like said before learn to quack first and foremost. The rest you can learn over time and probably wont use a whole lot. Listening to birds on the water/field is one of the best ways to learn what calls to use. Ducks DO feed call and hail call in groups. Sit by a corn field of birds, you'll hear every call in the book. Birds on the water do it as well. I heard a lone hen mallard calling her heart out on a small pothole. The key is knowing when to use the calls. In general as the season wears on less is better, but it's all about reading the birds which you will learn to do as you experiment with your calling. I've called plenty of birds using a few single quacks here and there, give it a shot.