specific headlight bulbs?

hey there all, just went out and bought some philips visionplus H4 bulb but havent installed them yet becasue i just want to make sure that they will fit, they have three pins to connect to and 60/55 watts. also how the hell do you change the bulbs, i cant seem to find a way to change them over.
thanks.

You just turn the plastic fitting sideways until it clicks off, remove old bulb, put new bulb in, put plastic fitting back into hole turn sideways, done.