Originally Posted by daspianist
I had looked/lurked quite a bit on this issue, and have found many helpful guides here on removing neck stains, but not so much on preventing them in the first place.
Someone on here awhile back suggested folding a sheet of paper towel in half lengthwise
and placing it around the back of the neck; then putting the shirt on.
I tried this tip and it works very well. The shirt collar covers the paper towel laying just underneath.
This summer in Toronto was a scorcher and on any typical ultra-hot humid day I went through 4 sheets of paper towel. No matter how much I sweat on those days my collars stayed stain-free.
Not very glamourous but it was discreet and it worked.