Hi Jayne,

The plunger works by creating a vacuum seal around the plug and forcing air down, ( downstroke) and up sucking up (upstroke)

Fill the shower with a small amount of water, just enough to cover the bottom of the plunger. Begin plunging with a forceful upward and downward movement. Most clogs only require about six good plunging rhythms. Lift up the plunger to see if the water is draining away quickly.