Pry the sprinkler shaft out of the center of the sprinkler housing, using the flat-head screwdriver. Hold the shaft to prevent it from retracting into the housing.
Twist the sprinkler head counterclockwise until the head detaches from the shaft.
Pull the basket away from the spray head to separate the two components.
Move the sprinkler head back and forth in a bucket of water to remove any debris that may be clogging the head. Carefully look inside the head to see if any particles are blocking the water jets. You can remove any you find with a toothpick.
Turn on the sprinkler valve for a few seconds to flush away any dirt that has fallen into the sprinkler housing.
Insert the new basket into the sprinkler shaft.
Twist the sprinkler head onto the shaft, turning clockwise until tight.
Turn the sprinkler system on and adjust the direction of the sprinkler if necessary.