now I shall have to search for where it was I saw it

yer tiz - hmm looks a bit 'temperamental'
To dye with avocados, you scrape all the flesh off the peel and soak them for a VERY long time (weeks) in either water or alcohol or
ammonia, depending on the color you want. The pits can be
crushed/chopped and used as well, though I have not yet done that.
While the peels are soaking, heat the solution every few days to
prevent mold; if mold appears the dye will turn brown. I used
alcohol, so didn't have to worry too much about the molding. After a
few weeks, remove the peels and add the fiber. I heated it, but I"m
not sure you have to; I'm a bit fuzzy on the details