If you paint it, you can't wash it in the dishwasher. What would you like to paint on it? Be sure to use a food safe paint.
Thanks so much!
If your cup is oven safe......you can use permanent markers and then bake them in an oven at 200 for 30 minutes and leave in oven till they become room temperature. After using them for coffee/tea
wash by hand. They will last a long time. I also put my old fingernail polish on a bed of water in an old tin turkey pan......hold the cup by the handle and dip only the sides not the bottom. Stand alone at least 1 hour ......I have even put the cups in the dishwasher and they were fine. I wouldn't do it too often.....if you want it to stay as nice as you made them.