Hi 1stime, I hope I can help you out here :)
Basically, buy him a good razor with good blades. That means one with 3 blades and, if you're feeling generous, a moisturing strip also; it helps a lot. Don't bother with electric shavers, they're expensive, volatile and no where near as close a shave as manual shavers.
What he needs to do is lather up with a reasonable shaving foam, or just get the face really wet with warm water; the former is better by far but if you're pushed for time water will do. First shave WITH the grain of the hairs, so shave downwards: from the side-burns down to the jawline and follow the jawline round to the chin. Small brushes, not long sweeps as then you'll probably cut yourself. Have the sink full of warm water ready and dip the blade in every now and then to get rid of any hairs sticking. For the chin just shave downwards from the mouth towards the neck. Underneath the chin is a bit trickier as there's no prevalent grain of the hair, so I just shave downwards towards the neck. With your free hand, pull the skin tight on the area you're shaving, you'll get a closer shave.
That'll do then, but if you really a want a super-duper close shave, lather up again then shave AGAINST the grain. Take great care and do it slowly as the chances of getting ingrown hairs are heightened. The same rules apply as stated above.
Once down, apply a good post-shave balm to all the areas you've shaved, as this will help prevent razor burn (painful) and in-grown hairs as it opens your pores up.
I really hope this helps....I imagine it's the same for shaving your legs really....not that I'd know. I hope I haven't been too patronising in this, but I do remember when I was a teenager wondering how the hell I should shave!