Before I even started or brainstormed how to make my marker, I did some research. This usually just consists of an image search, you can learn a lot just by looking at things, get different ideas, views, see how things look, work, etc. Searching the term bookmarks, just brought up a lot of normal paper/card markers, and while these may be cute, have poems, or whatever. I found They Don't Work!
Another thing I'd like to mention is a few months ago I tried making some corner markers that are made from envelopes, because everyone was raving about them and they were kinda cool looking.(monsters, hearts, etc.) I had the worst experience with this type, as I could not get it to stay put for the life of me.
Any ways as I was working I remembered that I'd bought a magnetic marker many moons ago, and it was actually pretty good at keeping a page, though these also tend to move some. I then searched for magnet bookmarks, found lots of tutorials, versions, and ways to do them, but I didn't really like anything I saw too much.
The idea came to me that I could do a braided marker somehow, so that's what I searched next. Again there was lots of braided ones, most made with ribbon, some had charms, others beads, and some even had loops to wrap them around the whole book cover. For the most part I couldn't tell how this type of marker stayed put, it seamed to me that the weight of the charms and such would cause the markers to slip out the bottom.
In the end I saw lots of bookmarkers and creative ways to make them, But I didn't want to do something that's been done a bunch of times before unless it had my own spin/touch. I settled on the braided type, and figured out how to prevent them from being pulled or slipping out. 'A Button' (works great if you have kids)