You are removing the power switch and leaving yourself (and others) with no way to quickly disconnect power in the event of laser malfunction (fire) or immolation (laser setting something/someone in the room on fire).
Lasers can be dangerous!
Lasers can be dangerous, even small ones. Never point it someone's eyes. Treat them like a loaded gun -- always assume it is about to turn on and always point it in a safe direction. Remember reflections can also do damage, so avoid reflective surfaces and wear laser-grade eye protection.
That said... here's how:
Bypass the tactile switch by shorting across it's longest dimension as shown below. It doesn't matter which side (upper pair or lower pair from figures perspective) you use as the short sided legs are tied together internally in most parts.