Attach the 3/4" stuffing tube to your stuffer. Your stuffer has two gears for gross movements (big motion) and fine movements (small motion). Use the gross movements to lift up the seal until you can remove the container.
Fill the container with your sausage, making sure to pack it in tight, so that you don't have any extra air in the meat. Extra air=Air bubbles in your cased sausage=bad
Place the container back into your stuffer and move the seal back down with the gross movements until you reach the meat (you'll hit a bunch of resistance when you do).
When the seal has reached the top of the meat stop your cranking and push your sausage casings onto the stuffing tube fully. Use the fine movement gear to slowly start pushing the meat to the end of the stuffing tube stopping before it comes out. Tie the end of your casing like a balloon. By doing this, you will eliminate extra air in your sausage.
Once tied, continue cranking with the fine movements pushing the sausage into the casings. It helps a lot to have two people helping with one cranking the stuffer and one holding the meat. I do this slowly to ensure the meat is filling up the casing to my desired thickness (brat size).
Continue cranking until all of the casing is used or you run out of meat and then tie off the other end of the casings.
You can twist the casings into links or leave it in a singular circular sausage.
To form the sausage into links first choose a starting end and figure out how long you want your link to be (a couple of inches, a giant wiener, the choice is yours).
However long you want the link, pinch where you want the other end to be and twist a couple of times. Continue this. Go along the sausage switching directions at each link (away from you, towards you, away from you, again and again) until you are done.
This might leave you with a slightly too big or too small link at the end but that's ok!