1. Regarding dye solution amounts, less is more.
2. Don't agitate dyed roving when rinsing, unless you really want to spend hours teasing apart 2 pounds of felted fiber.
3. Wear gloves when dyeing, unless you want your blue-ish/green-ish fingernails to scare the Kindergarteners - actually, quite a good thing IF it's near Halloween...
4. Record your dye solution formula (such as it is), because you never know if something incredibly ugly, e.g., 2 pounds of felted malformed dark green Coopworth roving is going to morph into something you actually quite like.