I guess I assume you're talking about sausage gravy to serve over biscuits. This is how I do it, although it is not something you should make if you are watching your cholesterol!

Brown some sausage (half pound or so) in a skillet and break up as small as possible. I like to let it cook so that some pieces are almost crispy. Once this is browned, reduce the heat and sprinkle about a half cup of flour over the whole works and stir in until all the flour is mixes with the fat and meat. Add about 3 cups of milk and stir until well blended. Turn the heat to about medium and stir until thickened and bubbly. You may need to add about 1 more cup of milk. Salt and pepper to taste and serve over biscuits. If your sausage is particularly lean, you can add some buter or oil when you add the flour if there isnot enough to moisten the flour. Good Luck!