I used to make jewelry, but the simplest stitch markers I’ve found to make are using the round end of a toggle closure. Walmart has inexpensive toggle closures and in the photo that I included, that’s what I used. They will fit up to size 10 needles. Then you just buy some ‘head pins’. The type that I used in the example have a loop on the end, which is where I attached the charm. Other head pins look just like stick pins, but longer to accomodate the beads. Maybe the toughest part (and really not that tough) is making the loop on the top of the head pin after you’ve strung on whatever beads you want. This is where you will attach it to the end of the toggle that will slide on to the knitting needle. I have found that I like to use inexpensive but pretty plastic beads rather than glass beads because they can be too heavy. I hope this helps. If I’ve gotten too basic, I apologize, but sometimes a picture helps. Let me know if you have any questions.