For the pork, you can use ground pork, but if you are grinding yourself, pork shoulder, or preferred would be pork belly minus the skin. Use the wagon plate (coarse plate) for a nice mince.
If using hog casings packed in salt, you will need to soak and rinse them following the suppliers instructions. If using dry hog casing, set them aside until needed, the just need a minute or two in water and can be used. You can also use collagen casings if you prefer.
Peel the garlic and mince well.
Add the ground pork, minced garlic, rice, salt, and pepper to a large mixing bowl. Using your hands, get in there and mix well.
Using the method of your choice, stuff the sausage casings. Once stuffed, use sting tie off the sausage into 1 1/2 inch links. Do not twist the links, just use the string and tie, tightly.
Once everything is tied tightly, you can either cook now, or leave to ferment for a few days. The fermentation happens with the salt and rice.
To ferment, use the fridge, there is less chance of spoilage of the pork. Place the sausage in a large bowl and cover with plastic wrap, place in the fridge for 2-3 days.
The fermenting is not really needed, you can prepare the sausage and grill the same day, no harm.
You can taste the sausage mixture and adjust as needed by first pan frying a small amount or microwaving a small amount.