To marble some paper is on my list since for ever. First I tried to marble with nail polish and it was a complete disaster. Then I found marble paint from Marabu (easy marble). There are several different colors and they are easy to use.
All you need is marble paint, water, a bin where you put your water in, toothpicks to mix the different colors, tweezers to remove the paper from the bin and some paper. I used a variety of different papers to find out which one works best - the thick watercolor paper worked best. The process is a little bit messy so I recommend to use plastic gloves (I didn't but will do this next time) and cover your work surface with something.
Start with adding water into your bin and then drop your paint into the water. You can leave the pattern this way or use the toothpicks to create a different pattern.
Put the paper into your bin and give a little bit of pressure to make sure the whole paper gets covered with paint. Then remove the paper with your tweezers and let it dry for a couple of hours. The thinner the paper the more curly it is. To flatten my curled paper I made a stack with thick books and layed my paper underneath. It helped, but you get the best results with really thick paper.
You can't control how the pattern will turn out so don't try to create a specific pattern. Just add paint and embrace the imperfection. I used one of the marbled paper for my art journal and I plan to use some for handmade cards and business cards.
In the year I'm 27 I want to create 27 handmade items I've never done before. I want to experience new material and try new techniques. You can follow my progress here and read more about how this project came together here.