Freeze venison and pig fat for better processing, but make sure it is not too frozen, and cut all into 1-inch chunks.
Feed chunks into meat grinder or food processor. Catch in a pan beneath. Try to mix a bit of each at a time so that the hamburger comes out with a good mix of fat with the meat.
If you are using a food processor, don't fill it up but about ¼ full and pulse it until you have a nice crumbled grind.
Once meat is well ground, add your salt, sugar, and herbs, sprinkling over the entire grind.
Mix well together with your hands, adding some turns of black pepper if you want a bit more bite.
Form into small burger-sized patties and lay out on/wrap with butcher paper on trays if you intend to freeze or refrigerate for later.
Alternatively, you could add to a sausage stuffer if you have one. Make sure your sausage casings are thoroughly rinsed and soak for at least 20 minutes. Place casing on sausage stuffer and add meat inside, slowly pressing into casings. Twist and cut off ends into desired lengths.
If cooking some immediately, heat skillet and fry on both sides over medium heat until a nice golden-brown colour.