Pretty much what skinnerback said. After I cut the meat from the bones, I put it in ziplock bags and freeze it. Then I set it out and let it partially thaw (usually the edges get a little soft while the core is still hard) so that I can cut it into strips small enough to go through my grinder. You do want the meat to be firm or it will get mushy when you grind it.
I think the theory is that freezing/thawing/freezing meat causes it to lose some nutritional value, but doing it once or twice isn't significant.
There are dozens (hundreds?) of recipes for breakfast sausage on the internet or in cookbooks, but here's the one I'm currently using:
Get a 12oz container of TexJoy sausage seasoning. Add 3 Tablespoons of Cayenne Pepper (more or less to taste — you might start with two) and mix well. That should season about 40 Lbs of meat, ratio it out according to the amount you have. Add about 1 Tablespoon of sage for each 5 Lbs of meat.
Voila! Breakfast Sausage
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