Did you leave the little ties on the hank? If you did, DO NOT PANIC. I've been here myself... here's how to fix it.
Find one of the two places where they tied a length of yarn around the hank.
Lay the hank on a table and expose that tied section.
Carefully separate each misaligned strand by moving it to the correct side of the tie. (I hope you're following me here.)
Once you have them all on the correct sides, pick up the hank by that tied area, hold it firmly with one hand and give it a good shake
Put an arm through the hank at the tied section.
Put the other arm through the other way as if you're crossing your arms in front of you.
Begin rolling your arms over each other and let the hank travel along.
After a short while, the hank will begin to open up. Periodically, hold the tied area again and fling the hank as if you're cracking a whip. Repeat the arm rolling technique.
Repeat these two techniques until the hank is all nice and neat again.
(I hope it works for you!)
NEXT time you're going to dye a hank, take some scrap yarn and tie 4 or more loops around the sides of the hank. Loosely though, you don't want to constrict the yarn any or else the dye won't get through. Just tie the loops loosely so they help keep the hank in order.