This weekend a friend and I did a little experimental marbling. The process is similar to tie dye, but marbling gives you more control and trippier results.
We gathered up the test subjects and soaked them in an aluminum sulphate mixture so ensure the colors don't rinse off, then let them dry over night. That night we also prepared our methyl cel solution so that it would be ready by the time we woke up.
The next morning our methyl cel was a nice jelly-ish consistency, our objects were dry, and we were ready to marble!
If you want to try marbling, I highly recommend Pro Chemical & Dye. Their website could use a little re-vamp, but the customer service is on point. Plus they send you (basically) everything you'll need.