We used two different methods. The first involved shaving foam and food coloring.
Squirt the foam onto a tray to the size and shape of your paper.
Using droppers, add two or three food colors (or liquid watercolors, which we also used).
Swirl everything gently with a skewer, a comb, or a feather into gentle shapes - not just big circles. And try not to make mud! This is one of those things where 'less is more.'
Now lay the paper gently on top of the foam and pat down all over with the palm of your hand.
Lift the paper and gently scrape off the excess foam into a bowl with an old credit card. Allow to dry. Beautiful!
The second method involves liquid starch, alum, and acrylic paint. Needless to say, our older campers tackled this one - and loved the results! We used the instructions found here: https://skiptomylou.wordpress.com/2008/05/25/marbelizing-paper/
You can use your marbled paper to make things like cards and covers or end papers for your own handmade books. Drew made these gorgeous book markers from both types of marbled paper.