The bookmark on the right is worked with continental stitch, and the one on the left is blank with a round of sc worked around the edges - which was a little tricky to do. I used size 3 cotton and a size B crochet hook, but I think I should of used size 10 cotton - it would of been a little easier to get the thread through the holes. If I make another one, I will go with the size 10.
For the crochet edge bookmark: put a sl st on your (real) crochet hook, insert hook into any hole, yarn over, pull through and complete as a sc. Sc in each hole on the straight lines, and 2 sc in each corner square around the piece. Join with a sl st to the 1st sc and end off. Tie the ends into a knot and then weave the tails through the sc stitches.
For the solid bookmark: using worsted weight yarn, work the piece using the continental stitch. Whipstitch around the edge and you're done.
Here's the graph for the crochet hook bookmark:
Thanks for dropping by - I hope you're enjoying your day. :)