To be dyed, the DMC floss must be wound into skeins. The diameter of the skein and the number of yards in the skein is up to you. I wind a thirty-yard skein. You may wish to wind shorter skeins until you feel more confident about your dyeing skills.
This is a small warping board, the kind of equipment a weaver would have. I wind my skeins on it. You can get the same effect by placing two kitchen chairs together and winding around the tops of the chairs. Once, with no equipment at hand. I wound a warp for a small loom around the knobs of the two dressers in the bedroom, with the warp threads crossing the room like a barrier. When the winding is done, my long weaving warp or your shorter floss skein is tied and removed, and you get your kitchen chairs back!
Here's the completed skein. The next step is to tie it.
This is how you tie a skein so it won't unwind. I've used blue thread here so you can see it clearly, but the actual tie will be in a fine white thread. I commonly use a fine crochet cotton or perle cotton. (What sort of leftovers do you have lying around? Use them!) To tie the skein, you will make a figure eight that weaves through the threads and ties loosely atop them. How many of these ties you put on a skein depends how you want to handle the threads in the dye. I tie two figure eights, one each on opposite sides of the warp.
Then I lay the tied skeins out on strips of nylon net.
I fold the strip of net in half, enclosing the skein, and stitch the packet closed. Some sewing machines will balk at sewing on this flimsy net. I experienced more balking when I sewed a zigzag seam. When I changed to a long straight stitch, which has proven to be quite adequate for the task at hand, the machine calmed down a lot. Experiment.
After stitching, I trim the edges down, and the result looks like this. Cotton on top, silk below. Now I have an easy-to handle package that will take my skein through, in order, washing, rinsing, dyeing, rinsing, washing and rinsing. You can wring the skeins out like a washcloth and they won't tangle or tear! It has simplified things immensely.
Seems like a big investment of time, does it? If you do not stitch your skeins into these nylon net package, you'll need to tie more figure-eight ties on each skein -- six or eight. And you will have to handle them carefully.
Decide how many skeins you will process at once. I do fifteen in a batch. You can space out all the tasks to this point -- wind a few skeins every day, stitch a few skeins into net every day, but from this point on It takes a certain amount of stamina to do all the necessary steps in a row, and you will need to have your wits about you when you sit down to paint your skeins. You don't want to be worn out at that point.
Wash the skeins. I do these in a big bowl in the kitchen sink using Dawn dish detergent. You can also do them in your washing machine, but I'm wary of the stuff in laundry detergent: softeners, brighteners. Dyeing outcomes are changed by virtually anything: the makeup of your water, the additives in your detergent, the temperature of your rinse water after dyeing. The good news is that I've never seen a skein of dyed embroidery floss that was utterly unusable! This isn't like draping the colors over your body and going to the theater -- ugly colors, horrible combinations will find a home in what you stitch, and they will often set off the other colors magnificently.
Hang your washed and rinsed skeins to dry. And at last you are ready to dye!