I have been dying silk scarves with Procion MX Dyes.
There are several online classes.
Marjie McWilliams teaches one [Silk Dyeing] at QuiltUniversity.com
It is well done and very reasonably priced.
Here are some close ups:
Colorhue silk dyes are an easy way to dyes scarves. They set instantly.
Less mess. Marlene Glickman sells these [http://silkdyes.com/supplies.html] as do several other vendors such as Dharma trading [http://www.dharmatrading.com/html/eng/10503535-AA.shtml?lnav=dyes.html]
Which do I like better?
They have advantages and disadvantages.
I always have Procion MX dyes on hand. And for dyeing yardages of fabric, I would choose Procion. And I now feel comfortable using them on silk.
Colorhue dyes are great. Quick. Less mess. Instant gratifcation. I have a little trouble creating deep saturated colors with the Colorhue dyes.
I'll probably continue to use both!