I was in your shoes just a few years ago. Grew up dove hunting but never ducks, then fortunately got into duck hunting at work on a few trips with customers. The easiest way to learn it and get better is just to simply go with people who've been doing it a long time. A guided hunt would be a good option, getting on a lease around houston where you could meet people doing it would also be a good idea if you can afford it.
As for general, applies to everywhere advice that I've learned both on texags and out in the field:
1) ducks are way smarter than dove. Dont move, keep quiet, try not to have the sun reflect off your face. This isnt dove hunting where you can yell at your buddies and wear a t-shirt with jeans and be good to go.
2) Calling, less is more, and dont even do it if you dont know what you are doing. You are far more likely to scare/flare birds off if you just start going to town on a call and dont do it right. Practice a lot, watch youtube videos or actual people using calls, then practice some more.
3) Decoys, find what works for your area, it will likely require some trial and error. Some people swear by mojos with the spinning wings, other wont hunt a blind if youre using one because they think it will scare every bird away. Reality is somewhere in the middle. So figure that out, and how many regular floating decoys you need. More is not always better, most hunters probably dont need more than a couple dozen, if that.
4) Scouting, if you have the choice of several locations (on a lease with multiple spots, several farm tanks/creeks, whatever) put the time in and see where the birds want to be. You can have the best setup in the world but if the ducks dont want to be there, they wont be there. Simple as that.
Im sure theres a lot more that Im missing so hopefully a few guys who have been doing it longer than I've been born will stop by, I know there's some on here.