Sand the napkin rings to remove any rough edges or any finish that may have been on them.
Use cardboard tubes to hold your napkin rings and paint them with Cornflower (blue) and Mother of Pearl (white). You will need 3-4 coats on each napkin ring.
In between paint coats, create your sentiment cards. Attach the rub-ons to white card stock and use a paper cutter to cut them out.
Cut colored card stock a little bigger than the sentiments (1/4" - 1/5" larger) and attach the sentiments to the card stock using your tape roller or glue stick.
Punch a hole in the upper left corner of each sentiment card. Loop the twine through the hole. Tie a bow at the top of the open ends of the twine.
Thin some Jet Stream (pale blue) paint with a small amount of water. Dip the handle end of a small paintbrush into the paint and dot onto the napkin rings. Allow polka dots to dry completely.
Insert rolled napkins into rings and insert the twine up into the napkin ring so that the bow pokes out the top and the sentiment card is displayed face up.