I use a water shredder. I just fold the paper a few times
and run it under warm water. Most paper these days turns
back into paper pulp when it gets wet PDQ.
Just twist the wet paper, and no one will ever be able to
see what was written/printed on it.
Mainly, I do that with junk mail. I never throw anything with
our names and address into the trash without “shredding” it.