This is the recipe that my (Italian) mom used to make her own sausage. This is for mild sausage. If you want hot you can add crushed red pepper to it. It's so much better than store bought, and a lot less expensive.
The pork should be coarse ground. I grind my own. If you don't have a grinder you can have it ground from any good butcher or meat department of your local grocery store. Do not trim the fat off. Your sausage will come out dry if it doesn't have enough fat. If the pork you are using is very lean you can add some olive oil to the mix.
If you grind your own first cut it into 1 to 2 inch chunks and then put into the freezer for about an hour. This makes it grind much easer and also helps to keep it cold while processing.
In a large bowl combine the ground pork and seasonings and ice water. Mix thoroughly using your hands. Cover and refrigerate for an hour or 2.
If you want hot sausage just add 2 Tbs. of crushed red pepper. (or to taste) I also like to add another tbs. of paprika to give it a little more red color. It makes it easer to tell hot from mild too
After you refrigerate it make a small patty and fry it. Taste it and add seasoning to taste if needed. Refrigerate again and repeat the tasting. You can repeat this as often as needed. Just keep tract of what and how much you add so next time you don't have to do this step.
At this point you can freeze the sausage in bulk, make it into patties and freeze, or pack into casings to freeze.
Most natural casings come dry packed in salt. To prepare for use first rinse in cool running water and soak for 15 minutes. Open one end of the casing and let warm water from the faucet run through the entire length of the casing. Cut into 2 foot sections. rinse only what you think you will need.
To pack into casings you will need to buy some natural sausage casings and have a sausage stuffing kit. Fill the casings loosely and leave 1 inch at each end. To stuff the casings first slip the open end of rinsed casing over the sausage funnel and tie. Feed sausage mixture into the funnel by hand or using your sausage stuffing attachment of your grinder. Follow manufactures directions if using attachment.