All depends how it is wired, looking at the diagram on the switch I would imagine that pin 1 & 3 are the Live Neutral in and 2 and 4 are the live and neutral out. When you press the switch you close the contacts this also enegises the coil shown across 2 and 4 and holds the switch in.
Are there wires connected to 5 & 6 ?, many saws nowadays have electro-braking to stop the blade when its switched off. This may use the 2 auxiliary contacts. As I say its difficult to say exactly without seeing it first hand but most competent electricians with some experience in control systems should be able to sort out for you. Shame I'm a bit far away.