Tiny me are a wonderful US site that do loads of free craft printables for children to use, and I love this Father's Day Book idea. It's full of starter ideas for children to complete themselves, so that they create a unique gift for their Dads, and I think this would be very welcome on Father's Day morning.
The books is called "The Most Amazing Daddy That Ever Lived: a very true story" and there's a gap for your child to fill in their name under 'Written and Illustrated by'. Pages include spaces for pictures and writing and pages like "My Daddy's Superpower is..." and "Daddy Makes Me Laugh When...".
All you have to do is join the mailing list, which you can un-subscribe from at any time, and then download and print the pages. You'll need a glue stick to stick the pages together to make the 'book', and the instructions are in the site. It's such a lovely idea, and a simple keepsake that will be treasured, and I think this is a free printable that is definitely worth getting.