I use a head set magnifier bought from the local HF or box store company and I line up the pin with the gizmo tool pin and presto!!  Automatically presses out the pins with an easy flick of the fingers turning the screw thing-a-ma-jig.

Just be careful to line up the pins properly and you will save yourself a luncheon's worth of bucks from the watch shop's charge.  To set the pin back in just use any other form of pressing it or lightly hammering it in place with almost anything.

It comes with half a dozen extra pin pushers including the one in the tool already.  Works very well and has simple instructions in the kit.  This will last me for a lifetime.  I've already sized four watch bands quickly without any problems.