I have a Jet 16-32 and paper changes can be challenging. The side against the motor is always the worst. The tool is hard to use but is the only way to go. You hook it in the hole of the spring loaded finger and flip the tool up on top of the drum. That holds the finger open. Wrap your paper keeping it tight and if possible reach down and get hold of the end of the paper after it is inserted in the slot where the spring loaded finger is. Hold the paper tight and move the Tuff Tool back over the side of the drum and that lets the spring loaded finger grab the end of the paper. Sometimes it is easier to do the side next to the motor first and wrap the paper around and attach on the open side last. That sounds backward but what ever works works.
The paper must be tight on the drum or it makes noise (a slapping sound), gets wrapped over it self and burns your work and ruins the paper. When running your work through the machine keep alternating from side to side and down the middle. This gives you even wear on the paper and makes the paper last longer. Also get one of the gum type sand paper cleaning sticks and clean the paper periodically to keep it from loading up. You must always use dust collection or the paper wont last till the water gets hot and will smoke you out of your shop and fill your lungs with fine dust.
Also important is that you have the right amount of the tail of the paper in the spring loaded slot. Too wide and the paper will not hold, too little and it slips out. You should have about the same amount of the tapered end through both slots the same amount. This is trail and error method but after you get it right a few times it will be simplier.