Changing lawn mower blades is a simple procedure that will take less than half an hour if the right tools are already owned.
The tools needed are in the second picture.
From left to right:
Sharp blades (see note), work gloves, ratchet and socket or a wrench (see note)
Sharp blades are not needed. If there is no spare sharp set of blades the time to change the blades will increase significantly because time will need to be added in order to sharpen the dull blades once they are taken off.
The ratchet and socket will be easier to work with than a wrench, but a wrench will work in the absence of a ratchet and socket.
Step 1: Finding a Place to Change the Blades
Depending on the type of mower being used, different places will be better than others. For example, a small push mower can just be flipped on its side on top of a cement pad after the oil and gas has been drained.
For a mower parked on top of a raised piece of ground it is mandatory to use the parking break.
1. Find a place to park.
2. Switch the parking brake to the "On" position as seen in the second picture.
3. Turn the engine off and let the mower cool if it is hot.
4. Place a block in front of and behind a tire as seen in the third picture.
WARNING: If steps 2 and 3 are not followed the mower could roll down hill and cause injury.