If the one chart is going to be permanent, I would first mount it to the table with spray adhesive
& then brush clear polyurethane
over the whole table top. 3M Super 77 is my permanent spray adhesive
of choice. I don't have a favorite brand for the polyurethane
. Just about the only thing that cleans up 77 is turpentine. Be sure to have some on hand.
If you want to be able to change the chart, then post #7 sounds good to me.