Side craft: I saw Romi Hill do this on Instagram, so I wanted to try it.
You know those bath poufs for scrubbing? They’re made of a long tube of nylon net, which is pretty much the same as a very long yarn sleeve. I had a pink one at home, but decided that I wanted a more neutral color. This pale green was as close as I could get to neutral. I snipped the string that held the center together, and was rewarded with 3.5 yards (3.2 meters) of usable tube.
I like mine to be about 5.5 to 6 inches long; they shorten up when stretched. I’ll get at least 20 sleeves from this inexpensive (less than $2) pouf. I’m finding that these are a little looser/wider than the commercial ones, but they’ll do. (Edit: Romi says that steaming them can make them a little narrower/tighter.) Why do I like these sleeves? They keep the ball tidy, no yarn unwinding from the outside of my center pull ball.
Do you prefer a center pull ball/cake, or working from the outside? I usually like center pull. But I’m knitting one of my projects with Knit Picks Chroma, and it’s easier to knit from the outside of those balls, no sleeve needed.
This monogamous knitter just said “one of my projects,” haha! I kind of have two right now. They’re related; the green one is an brioche and assigned pooling project but I made an math error in my decrease rate, whoops! It was bottom up, so while I was re-figuring, I also decided to make it top down. And to save the yarn from many more froggings while I work things out (it’s holding up amazingly well through several different design ideas), I decided to do a non-pooled version with the Chroma.
I’ve just frogged the green project, so I really do have only one project on my needles!
PDXKnitterati 
Such a dickhead am I, Michele – I have thrown TWO of these away, of recent months.
☹
What a clever idea for using the inexpensive bath puff. And you get the benefit of seeing a bit of the yarn cake. I have several ball sleeves but they are fabric so they hide the yarn ball colors.
Very clever as Knittingissofun said. Do they unravel over time since they are cut?
I usually knit from the outside of the yarn cake.
What a great idea. I prefer to pull from the center of the cake, so a poof might be in my future.