The easiest way to do this is to use the standard flat head as a mini pry, simply insert into the spring as shown above and LIGHTLY pry it away from the pad the minimum needed to allow the pad to be lifted off its guide pins. Again. Use the absolute minimum needed force when prying or you can bend the springs and that risks replacement. Note the pad shims on my car remained with the caliper, also take this time to confirm all pistons are fully retracted. Fingers are enough if they aren't