Get a good box call and a slate call. If you're going to use mouth calls, get them now and start practicing. To be successful at turkey hunting, first thing is first you need to be good at calling and sounding like a real turkey especially if you're hunting birds that are pressured, which most are. I use a couple Primos slates, a Primos box, a couple of HS slates, and half a dozen mouth calls.
If you're bow hunting for them, get yourself a blind that is big enough to draw your bow in, make sure its black on the inside. Wear black when hunting them out of a blind. I use a Double Bull Darkhorse and its awesome.
I didn't use decoys much when I gun hunted. I only bow hunt them now and can honestly say that investing in some decoys that look like the real thing is an absolute necessity to consistently bring birds in to 10 yards or less. Brands like the Dakota Jake BTD, Dave Smith Decoys, and the Avian X Zinks are the best out there. I've had mixed results with the B-Mobile and Pretty Boy strutting decoys, just because strutters usually only bring in more mature gobblers. I use a Dakota Jake now with an Avian X feeder and Avian X upright. Works awesome.
Turkey hunting is a crazy sport and there are so many options out there and keep in mind what works for me may not necessarily work for you. Everything I learned turkey hunting came from experience and I didn't even bring a bird home until my 3rd of 4th year of hunting them.