1) Insert the "REMOVE" side between your tyre and the rim.
2) Lever it to get the tyre out in this location
3) Push on the tool to get the side of the tyre fully out
Tips for putting your tyre back in:
1) Insert one side of your tyre into the rim by hand.
2) Insert the inner tube into your tyre, starting with the valve.
3) Insert the "INSTALL" side between your tyre and the rim.
4) Push the tool to fully insert the second side of the tyre into the rim, making sure not to pinch your inner tube.