Before cutting your chain it is important to remember a master link can only be joined by two internal links. If you are unsure, just take a look and any exposed plate on the chain is the outer and you will need to line up two inner plates.

Once you have decided which link you want to break you will need to grab your DRC Chain Breaking Tool and clamp it onto the correct chain lined up with one of the two pins you want to drive out. Once it is lined up simply drive the pins out with the chain breaking tool and remove the excess chain.