If you're in places like Kamakura’s Komachi Dori or a place that asks you not to do it, just don't do it. It's not seen as good manners normally so it's best to avoid in general....

There should be a separate day for 古紙 koshi or old paper like newspapers, cardboard, etc. I would look up your ward/city and 古紙 and see what day it's collected and if there's a special place f...