How do you fold Tubolitos?

If it’s like any other tube then you grab the valve stem and then pull on the rest of the tube until you’ve grabbed the complete opposite end. Then you start rolling as tight as you can from that far point. You’ll have to let air out as you’re doing it but it’s not hard, a rubber band or a strap helps to hold it together if you find yourself unable to manipulate it. And when you’re done just wrap it up tightly in/with something and put it where you want to keep it.
However if these have sealant or something in them then I’m not sure as sealant makes it impossible to get all the air out without also pushing the sealant back out of the valve stem.