How do thread a bobbin on a singer golden touch and sew model 620?

The bobbin is wound in the bobbin case. You open up the slide plate and push the little lever with the bull's eye on it all the way to the left. Then you thread the needle with the thread you want on the bobbin, then pull a few inches and wrap the needle thread around the knurled knob that holds the foot onto the shaft (to keep it from slipping.) Then you push down on the foot pedal and the bobbin fills from the needle thread. Don't overfill the bobbin or it won't wind out properly.