Paper and  fabric are treated similarly, though each has its peculiarities.  I have been marbling for over 15 years and tried many, many products and techniques.  I have settled on the procedure I find the easiest to set up and that most reliably produces stunning results.  Dozens and dozens of workshops later, I have yet to tire of seeing the delight in students' eyes as they view their first piece of marbling!  It's always a pleasant surprise.

The products I use are all water-based and non-toxic and I have used them with children countless times.  Alum is used in the pickling industry and is  the mordant, or fixative, allowing the pigments to bond permanently to the surface.  A solution of alum and warm water is mixed together and the fabric or paper is pre-treated with this, dipped in and then dried.  When I'm doing a large batch of fabric, I soak it all at once in the alum solution then throw it in the dryer, removing it while it's still slightly damp and pressing dry.  Paper can be hung on a rack and does not need to be pressed before marbling (although it can be).  Once pre-treated, fabric and paper can be stored for many weeks before marbling, allowing you to prepare conveniently, bit by bit.

The marbling base is a fine-grade clear methyl cellulose powder (like wallpaper paste)  that is mixed with water.  1 tsp. of ammonia is added per gallon of marbling base and this gives it excellent clarity and stability.  For many years I used carageenen which needed to be mixed 24 hrs. in advance of use and was a transluscent golden color.  Methyl cellulose can be mixed 15 min. before use and its clarity allows for truer "reading" of the pigments on the surface.

The tray in which you place the methyl cellulose base determines the size of fabric or paper you can marble.  A tray can be an aluminum basting pan or a child's swimming pool!  The base solution need only be about 1" deep.  My husband has made for me custom-size wooden trays with shallow sides that I line with plastic in order to marble silk scarves, for instance.

Many different water-based pigments can be used, just ask your supplier for those pigments especially designed for marbling.  Some suppliers who offer marbling pigments are, Dharma Trading, ProChem, Inc., and Rupert, Gibbon & Spider (Jacquard Products).

I usually have students set up the following way at a table in front of which they stand:  to their left, their pile of pre-treated, uncolored paper or fabric; in front of them, their marbling tray; above that, the various bottles of colors; to the right a shallow tray of rinsing water and to the right of that (or behind as space allows), a stack of newspapers to be layered between finished pieces.

Plastic squeeze bottles of pigment with a tiny hole in the top are shaken above the methyl cellulose surface so that small drops fall.  No squeezing pressure is required.  One at a time, 2-5 colors are shaken over the whole surface.  Colors do not mix on the surface, rather they will remain side-by-side producing the effect we know as marbling.  I do not recommend more then 5 colors (but all art "rules' are made to be broken!) because the surface can become muddied, not because the colors mix but because fine lines of many colors together are "mixed" by your eye and will "read" brown. 

The visual effectiveness of most design is enhanced by contrast.  Use the background color of your paper or fabric (often white) as the negative space.  You open this space by using the Colorless Extender, and swirling other contrasting colors through it.

To get pastel colors, use less pigment, for more intense colors, more pigment.

Once the surface is covered with pigment, it's time to swirl the design.  Using hair picks, toothpicks, bamboo skewers, or the utensil of your imagination, lightly "draw" across the surface of the pigments.  You do not need to dunk deeply and you do not want to move so quickly that you set up a wave motion that will change your design (you can experiment with this later!).  Draw lines in one direction all across the surface and then change directions and proceed across again. 

There is no great rush here, move steadily but unhurriedly until your design is pleasing (less is often more!).  Make sure your hands are dry when you pick up your paper or fabric.  Drops of water will interfere with the fixing process, leaving blanks on the surface of your design.  Gently place your fabric or paper onto the surface of the methyl cellulose covered with your marbled design.  You want to position it from the center outward, forcing bubbles out as you go.  Fabric will drape and fall naturally while paper needs to be pushed just slightly into place.  With practice you can do this in one smooth motion.  Until that time you will probably have "hesitation lines" across your design where your movement stopped and allowed the pigment to "back up"  briefly.  Not to worry because, first, no one else will notice it and second, it's gorgeous anyway!

Lift your marbled piece off the surface once it's had enough time to thoroughly come in contact with the pigment.  It does not need to linger, in fact the reaction happens upon contact, and leaving, especially fabric, on the surface serves only to soak up more methyl cellulose that will then be washed away.  Hold your marbled piece over the tray to let some of the  unused methyl cellulose drip off.

Place your marbled artwork into the tray of lukewarm water (the temperature is for your comfort, not anything to do with the process!) and lightly swish water over the surface until you can feel it becoming less slippery.  This indicates the methyl cellulose is removed and takes 20 second or less.  Then lift it out of the water bath, drip for a moment and place it on newspaper.  You can layer the marbled pieces and newspaper without concern for the newsprint transferring--it doesn't.  This keeps your post-marbling area fairly small, as opposed to having to set up a drying rack for each session.

As you prepare to marble your next piece, do not clean off the surface of the methyl cellulose.  Instead, swirl the colors that remain on the surface until they are fairly evenly distributed.  Then place your new color scheme and proceed to swirl as you did previously.  The "left over" color will work subtly into the "background" of the new piece and some pleasantly surprising results occur, creating greater depth to your design.

I hope this helps you get started with marbling.  Given that it's such a visual art and is so much easier to demonstrate than describe, I do recommend a workshop, wherever you can find one.  There are many fine teachers sharing the excitement of this beautiful and intriguing technique.  If you have any further questions, please feel free to contact me.