As I start a new project I'm usually chain piecing a lot of short seams so I'll put in a partially full bobbin to do these. My machine sets reminders until the bobbin is down to 8% which is actually still quite a bit of sewing left to go. I like to keep track of how many seams I'll get from that last 8%. Kind of a game really. I keep my thread stored with its corresponding bobbin attached. Bobbins are filled for the project, but the partial bobbin attached to the thread spool is the first to go in the machine. Another thing you can do is load the bobbin up top for the top thread where you can see it, and use it up that way.