Snowboarder hat

The pattern I am trying to follow says to join ear flaps: Turn work & cast on 19 sts. Turn back & knit across 25 sts. from 1st ear flap. Turn work & cast on 8 sts. I have not encountered this term "turn work". It is done in stocking st. It is a Bernat pattern. Could you possibly explain please?
With much appreciation, Arlene