Re-dyeing Black

I am working with 80% superwash merino wool, 10% cashmere, and %10 nylon worsted weight. I’ve knitted about five inches of my second skein -knitting a skirt. The black dye is coming off on my hands and is a now a lighter black color. When I’m done can I dye it all black so it’s matching? How do I keep it from bleeding on stuff when done? Just wash in cold?

Thank you,

Karin

Welcome to KH!
Usually dye is set with heat and vinegar or citric acid. There are numerous videos and tutorials online, for example:

You might try a couple of swatches first to see which technique works best.

Thank you! This helps a lot