Wash the avocado under cold running water. Try to rub it with your hands or if you have a food scrub brush go ahead and use it.
Cut in half. Use a sharp knife and cut the long way in the middle. Rotate the knife and avocado as you go. Make sure to take your time so you do not cut yourself.
Take the blade of the knife and stick it into the seed. When it is stuck in the pit rotate it to remove the seed.
Slice the halved avocado into more pieces. What you are doing is really quartering the avocado.
Peel the skin off the slices that you made.
Video
Notes
Tips - Use a kitchen cloth when you grab the seed to remove it from the knife. This will make sure you do not get cut.