Let's start out with the tube.
I didn't take pictures step-by-step of the rest, but I did include a video, so I hope it makes sense.
Sorry if my fingers got in the way. Here's the basis of it. On the end with the clipped corners, bunch a little bit of fabric over your stick (pencil with erasers work great because the fabric kind of sticks to the eraser). Then shimmy a little bit of fabric down until you can just pull a good amount over the stick. Then just pull the rest. Leave your stick still in there and poke out the corners, then let your stick fall out.
Let me know if you have any questions!