The most straight forward way to remove keycaps from a keyboard without a specific Keycap removal tool, also without causing any damage to the keys is to use to plastic cards such as credit cards.
Push the corner of each card under each side of the key that you wish to remove.
Then push down on the oposite end of each of the cards.
This will cause the key to pop off of the keyboard.
Be aware that the key may fly up off the the keyboard at a considerable rate. So be careful not to loose the key.