Friends of mine have the said boiler, with permanent pilot. Remove/open the lower panel at the front, you should see a big grey knob and a smaller red? button. Press and hold in grey knob whilst repeatedly pressing red button. Pilot flame should ignite. Keep grey knob pushed in for about 30 seconds, then slowly release. This should establish the pilot flame. If it doesnt ignite then you will need someone to look at the boiler.
Switching it off will not extinguish the pilot flame, it only stops the boiler from running as it requires an electricity supply to operate. Extinguishing the pilot can only be done by either turning the grey knob, or isolating the gas supply.