>There are many ways to decorate a mug (coffee cup).
If you have a digital photo you would like to have printed on a cup, you can see if your local photo lab (look online too) as well as your local printing shop does this. If you want to get fancier, you can also add text to the cup or even use computer software to make a ‘label’ to be printed onto the cup. Make sure you check your local print shop or photo lab before putting work into your cup as they may want you to make it a special size.
If you prefer to paint your own cup, see if there is a studio/store nearby that has special unglazed (doesn’t have a shiny finish) cups and paints for you to use. You can paint the cup in their studio/store and afterwards, they will glaze it. (A clear finish that makes your cup dishwasher safe and protects the paint.)
This activity promotes creativity.