I wonder if sun-dried sneakers always turn yellow? Is there any remedy?

After washing and drying, cover with a layer of toilet paper. It doesn't need good quality, as long as it can absorb water. After drying, you will see some yellow marks on the paper, but it is very white. My colleague told me. I tried.

It is said that the worse the paper, the better, because some white powder will fall on it. . . My colleague said that.