The first step in creating a natural dye for wool, or whatever you hope to add colour to, is to gather the plant materials. In some cases, this may be the root of the plant. Choose the blossoms before they begin to wilt and dry on the plant. Some common, easy to find dye sources are pokeberry, goldenrod plant, marigold, turmeric root, crushed acorns, and pomegranates.
You can now place your fibre into the pan and encourage it to submerge and soak up all that colour.
Keep it to 70c for at least half and hour and see how much colour has been absorbed, leave it longer if you'd like to try and get a deeper colour.
“Often I will turn off my pot after half an hour and just leave everything till the next day. Remove the fibre and rinse very well, then allow it to dry.”