Reading is best with nature, so take a little bit if that with you with a birch bark bookmark. The calming outdoor themed pattern of the bark is perfect; you can write on it, peek a layer off, and most importantly it's thin enough to function as a bookmark.
Step 1: Cut Your Piece
*Do not cut from a live tree, it can harm it**
From a piece of fresh cut birch, cut out a bookmark in your desired shape. I had some scraps lying around, so I used that.
Step 2: Size and Read!
You may want to peel back a couple layers of the bark in order to have a clean surface, which won't leave stains on your books, and thin the bookmark down. Enjoy your bookmark!