This video is a bonus for the online sewing course, Learn Fashion Sewing. You can find it at www.mariadenmark.com/shop/lea....
A set-in bobbin, usually found in older mechanical sewing machines, is a bit different from threading a drop-in bobbin. You have to put the bobbin into the bobbin case outside of the machine, pull the thread in place, then insert it into the machine. After that, pull up the thread with the needle before you start sewing.
And make sure to check out the PDF guide for detailed, step-by-step instructions.