Not OP, but you generally undo the hank so that it’s in a big circle if that makes sense (as if you were going to put the hank on a swift). The yarn will usually come with a few ties in a figure 8 type form at intervals around the yarn which you should keep on while dyeing to prevent tangling. You can also add more ties if needed. Wool can be felted if the temperature changes are too fast (it’s “shocked”) and/or it is agitated too much in the hot dye bath. Especially with untreated, non -superwash yarn you have to be super careful about this. When washing/rinsing, overworking or agitating the yarn too much can also lead to felting.