For example, these little smudges...
Thor is obviously having a bad hair day... but it's certainly a great creativity-stimulating activity for kids of all ages to see what they can make from simple prints.
The activity is super easy. The only items you need are a washable ink stamp pad, markers, paper, and water and a towel to wash ink off between stamping. Finger paints may also be used but they will take longer to dry and may be a little harder to draw on with marker.
You can think out what shapes you want to make or use random dots then see what shapes your imagination makes of it.
Whatever route or medium you choose. Fingerprint painting is a delightful activity for children from ages toddler to teen, and a lot of fun for adults, too.