I have two of those lazy Susan type cupboards where the roundish shelves
just sort of go around and around. The cupboard is not a complete circle.
I had previously lined them with white Contact paper but that didn't work so
well. I couldn't get a piece that was the right size so I wound up piecing
some together. It looked like crap. I decided to remove the paper in the
flour cupboard after I discovered the weevils. That cupboard has since had
pretty much everything replaced except for the salt.

The other cupboard has mainly canned goods but the liner is old looking and
starting to rip.

I have bought some of that spongy liner with the holes in it in the hopes
that it will keep things from sliding. One problem I've had is stuff flying
off the sides as the shelves spin around.

But how to cut it? This might be easier to install because it is more
flexible. I had purchased some white liner online that just didn't work at
all. It was very stiff and slick and even when cut in pieces there turned
out not to be enough of it. I am not sure the stuff I have now is big
enough to be able to put just one piece in. I don't really know how to
explain it but the curved design is baffling me. Also the fact that I can't
access the entire cupboard at once. I can only get to like...half of it or
so.

Any ideas? Or hmmm... Maybe I could pay my nephew to do the lining for me.
He's had a heck of a lot more math than I have.