My friend Karen and I had a play date a few weeks ago when we dyed some embroidery threads for her to use. It was part project, part experiment.
For starters, I wound up 10 yard skeins of 60/2 six strand silk floss (for embroiderers, that's roughly equivalent to Soie d'Alger). We decided to work with a scarlet/fuchsia colorway using Sabrachron F dyes. The advantage to the Sabrachron F dyes is that you don't need to use hot hot water to set the color - very hot tap water will do.
We started out with a 1% dye stock solution of each color, then mixed them in these proportions to get variations in hue: 90/10, 80/20, 50/50, 20/80, 10/90.
We prepared cups of water and added the mixed dyes to the cups in amounts that varied from up to 6 ml to as little as .6 ml. That gave us our tints.
We literally laid out the cups in a grid on the table to keep track of what was what.
We added our little skeins and stirred and soaked them for a while, the rinsed and dried.