One day, I decided to teach my kids how to make bookmarks. This was to solve their habit of putting their book open-side down on the table so they would know where they left off reading. Plus, it was a fun and easy activity to do. I did this when I was a child. My mother taught me how, too.
You do not need a fancy paper. I wanted to use a hard specialty paper . But we did not have one available. So, I grabbed the used white folder that we had, pens and pencils, coloured pens, scissors, yarn and most specially, a ruler. I was familiar with rectangular bookmarks.
My kids had other ideas. They did not use the ruler and went ahead with drawing anything they can think of. Kids are amazing because they are spontaneous. They just go ahead and draw, and do not worry about symmetry, proportion, being realistic and etc. Oftentimes, these rules hinder the adults from drawing.

My kids draw their favourite food free hand. The older one draw a pizza, hotdog bun, ice cream and candy by using a sign pen. These are simple sketches. The younger one drew popsicles, birds, ducks. They used colored pens to color their drawings . Then they cut around the shapes.
I showed them how where to punch a hole and how to make a tassle. We had yarns available. Any ribbon would do. They followed the instructions- punched a hole and put in the tassle. And viola! a bookmark!

As it turned out, they were the ones who taught me how to make a creative bookmark!
Yes, bookmarks do not need to be rectangular, or with a pattern after all. I hope I have inspired you to make your own bookmarks, in any way you want. Great for holiday gifts, too.