If your mist head is spraying in an abnormal pattern it is likely clogged. With the sprinkler running, grab hold of the stem (the part sticking out of the ground) of the mist head either with your hand or a pair of channel locks. Have someone else turn the water off if you are doing this by hand. Holding the stem, remove the nozzle, which is the top inch of the stem, by turning the nozzle to the left. Remove the screen inside and rinse it with water, it is often helpful to flush the whole head out by turning on the water with the nozzle off and screen removed. However, be careful that you don't get drenched in the fountain that will occur at this open head when you turn the water on with the nozzle off! Replace screen with the pointed end down, rescrew the nozzle back on by lining up the threads and turning it to the right until is it snug. Gently allow the head to retract back into the ground, checking to make sure your nozzle is pointed in the right direction.