Disconnect the spark plug wire
Tip the mower safely and secure it
Wear heavy gloves
Mark the blade orientation
Block the blade with a piece of wood
Loosen and remove the blade bolt
Remove the old blade
Inspect the blade adapter and mounting area
Install the new blade in the correct direction
Tighten the blade bolt to the manufacturer’s torque specification
Recheck that the blade is secure
Return the mower to its normal position
Reconnect the spark plug wire
Test the mower briefly before regular use