Go gradually. Read some, do some, read some more, do some more; repeat.
If you find yourself tempted to present a lesson, or to teach, feel that feeling and refrain from it. If your child asks a question, just answer the question. Answer it in an interesting way if you can. Look it up if you need to. Don't turn it into "a lesson."
If a child asks a question he might ask another one. Be prepared for one question to turn into fifteen of them. Be prepared for it not to.
from "Beginning to Unschool," page 36 or 39 of The Big Book of Unschooling
photo by Roya Dedeaux