That depends on how you wide you want the segments to be: the easiest option is to hold the end in between your fingers and carry the end around your elbow, back up, over the thumb, down round the elbow, back up over the thumb.... you get the idea. That will, however, give you quite short sections of dye: it will come out with quite a variegated effect.
As far as the how-to-dye goes, I find it works best if I arrange the wool in a vertical line and space the dyes from light to dark along the length. Then wrap it in clingfilm like a Christmas cracker, coil it into a pyramid with the lightest end at the top and steam it for 20 minutes /pop it into the microwave for 2/3 minutes: then drop the wool straight into a sink full of hot water and unwrap it in there once you're sure it's done. Pull the plug, pop the wool into a pillowcase, tie the top and spin it in the washing machine: no cold water involved in any stage of the proceedings apart from mixing the KoolAid. But then, I dye more roving than I do yarn, so felting is a big concern for me.
Roving I don't normally soak beforehand, but with yarn I probably would. Have you seen the stickies?
As far as the how-to-dye goes, I find it works best if I arrange the wool in a vertical line and space the dyes from light to dark along the length. Then wrap it in clingfilm like a Christmas cracker, coil it into a pyramid with the lightest end at the top and steam it for 20 minutes /pop it into the microwave for 2/3 minutes: then drop the wool straight into a sink full of hot water and unwrap it in there once you're sure it's done. Pull the plug, pop the wool into a pillowcase, tie the top and spin it in the washing machine: no cold water involved in any stage of the proceedings apart from mixing the KoolAid. But then, I dye more roving than I do yarn, so felting is a big concern for me.
Roving I don't normally soak beforehand, but with yarn I probably would. Have you seen the stickies?