My favorite way of decorating Tyvek is to use a foam cosmetic sponge dipped in acrylic ink. I then evenly smooth the color over the Tyvek, rubbing it in with the foam sponge.
It's best to work on top of some scrap paper and to wear vinyl or rubber gloves (I like the close-fitting kind, not the dishwashing kind).
Rubbing an even layer of the ink into the Tyvek brings out the patterns of its non-woven fibers. And one of the nicest things about acrylic ink is that it doesn't leave any discernible texture or tackiness--perfect for book pages. It just soaks into the Tyvek.
I've used it for accordion pages and small book covers. Most of what I've read claims it's archival, although I think nobody will know for certain until it has been used for more decades. Keith Smith cautions that some binders are skeptical, warning that the plasticizer in it may eventually dry out and shatter. That said, the stuff is used to wrap houses and it's a popular art material. I just use it and enjoy.
This shows a little gift book I made a while ago. The cover material and the pages are paste-painted Tyvek. I wish the photo could convey its tactile quality--very sturdy, yet people seem to like to pet the covers and pages.