First thing I'd do is learn how to use the lightmeter. Usually it's a case of setting the ISO (the ISO of the film in this case being 400) and then taking an incident or meter reading of the subject you want to shoot. All it'll do is display the aperture and shutter speed you need, to get an accurate exposure.
There's quite a few threads on home development around this forum, and a few guides through google too. So it should be easy enough.
As I say, grab a roll of Ilford HP5 (you can find it at 7dayshop) - and that should be a good start.