Really nothing too it, best piece of advise I can give ya, ask an indian, they have used them far longer than I
They ar really easy to make. First, go the the grocery store and buy the smallest turkey wing you can find. I like to get the smoked ones, they taste good
These are all three of the bones you need to make the call. The big one becomes the "bell", the bigger one of the two wing tips is the second one and the smaller bone of the two tip bones is the end or the one you put inot you mouth. Cut the ends off of all three using a hack saw or band saw, the will can can splintle so be careful. Next boil the meat out of the bones and you can add some household bleach to the water so it will whiten them up a bit( if desired). Aften they a boiled, 15 or 20 mins. let them cool off then with "something small and pointed" like a coat hanger, get all the meat out of the bones. More you get, the better the call will sound. After that you sound be able to fit one into the other, about 1/2" will be fine. I use two part epoxy to glue the three bones together and you can let your imagination run wild with any detail you wish to put on the call. Lanyards, beads, colored wrappings, you name it, it's been done. Once you go throught the process on your "store bought" wing, use it to kill the wild one and the smaller the bone the more like a hen it will sound and the more you get your hands on, the more you can change the pitches, big bells with small mouth pieces, two bones instead of the three piece call. They all work and they are all good, just some are better than others! Good Luck& have fun