Watch tool tutorial
Inside the strap, you will find small open holes. This is your starting point. NOTE: Make sure not to start from the screws. This can cause the screws to break.
Next, place the strap into the provided tool so that the pin can be pushed out properly. NOTE: Make sure to hit the hole/pin precisely, otherwise, you may break or bend the pin on the tool.
When the desired number of links has been removed, insert the pin in the same way you removed it. If the pin is still slightly protruding after this step, you can press/hammer it completely into the strap.