Instead of buying an oversized hallmark card...cut up a bunch of paper--hand them out--collect them--roll them up--and stick them in a mason jar.
The trick is to use a good palette of colorful paper--a pencil to help roll them--tape to close them before you tie the ribbon.
To make it easier for me to keep a uniformed look on the outer edge I stuck a piece of cardstock paper in the center of the jar. You don't even have to tape it in, just drop it in and let it conform to what's already there. So easy peasy.
I <3 mason jars--endless possibilities!