This is longer than it needed to be, but I couldn't help myself in talking about how I would thread my fly tying bobbins for 20 years.
You can skip past that, and the video shows how to use two different tools to thread your fly tying bobbins. If you weren't aware of these tools or not sure how to use them, this will be helpful. Please don't wait 20 years to figure out there is a better way........
https://www.youtube.com/channel/UCs5M_I1jgKDm0cblvU0JSIA/?sub_confirmation=1