Cover your work area with plastic. You may also want to wear gloves because this is a messy project.
Wipe the washers with rubbing alcohol. (isopropyl alcohol)
Start placing a couple of drops of alcohol ink on the washer.
Use a cotton swab to dab the color around. You can also place ink on a cotton pad and dab it onto the washer.
Try a light spray of rubbing alcohol on top to see how it disperses the colors.
Continue to play around with the inks until you reach a look you like.
If you hate it wipe it all off with a paper towel and isopropyl alcohol and start over.
Once complete allow the ink to dry for several hours or overnight.
Next give it a couple of coats of varnish spray, waiting at least 30 minutes between coats to protect the ink from scratches or chipping.
Finish by placing the small washer on top of the large washer.
Cut the cording to the length you want the necklace to hang.
Fold the cord in half and thread the folded end through the washers from the top.
Then thread the ends through the loop and pull tight.
Tie the cord around your neck and enjoy.