You can "clean" it with a J-cloth and a bowl of soapy water if you want!
You can "maintain" it using several professional techniques, depending on what the customer wants, what specific situation it's in etc. I don't know of any dedicated courses, but resilient floor maintenance is covered on some hard floor training.
For domestic work, you'll either be working on a floor in relatively good nick that the customer wants to keep on top of, in which case it's a doddle. Or you'll be looking at a floor that's covered in scratches and scuffs, which collect the crud so it looks like the scratches are black. Get something pointy and scrape this crud out and show it to the customer!
It's very rare in my experience that Amtico/Karndean etc gets cared for properly from day 1. Most customers seem to think you just put it down and that's it, ignore it forever

Fitters/suppliers are as much to blame for being ignorant - they supply it, they should be able to at least advise that flooring needs maintenance. But I suppose they don't, because they fear that the customer will perceive the flooring as being more expensive.
Anyway, I'll quit griping...
The best way to care for Amtico is by keeping up a good level of protection, provided by a sealer (Amtico call this their "dressing"). Amtico do come out with some guff about the top layer of some of their ranges being a "wearing layer" and it doesn't need anything on it. Balls! Once it's scratched, it's scratched, full stop. Let the sealer take the stick, and keep it maintained to keep the floor looking great and easier to clean (those are the key benefits to sell this work with).
The first time you work on any vinyl tile floor you should give it a real good seeing to with a stripping solution, just in case it has any sort of sealer on the surface. Use nothing coarser than a blue pad, get it nice and wet and let it dwell but NOT DRY OUT. Keep the solution moving around, only work in 10-15m² areas, maybe a bit more if it's a big open space.
Rinse off thoroughly with extraction equipment, with citric acid or something to provide similar acidity in the rinse water. Stripping products are moderately high pH - You need to make sure you bring your pH back to around neutral, otherwise you'll affect the sealer when it gets applied, it'll go milky.
You need to dry a small area of floor before wetting it with a drop of de-ionised water and applying your testing paper. Don't test it with the acid rinse water from the machine, you'll get a false reading! You can buy a little bottle of DI water and keep it on your van, doesn't take up much room.
After you've done a few of these jobs, as long as you don't change your products or methods, the pH testing will be a formality, you'll know it's right before you even check it.
So, clean floor, neutral pH, totally dry - give it 3 or 4 coats of proper sealer, not the overpriced crap that Amtico sell. Their stuff must be between 15 and 20% solids, pro products for this purpose should be around 25%.
Advise your customer several things (if you can stop them from grinning at their "new floor" and telling you how wonderful you are):
1) This isn't a 'permanent' coating, it is a "sacrificial layer" that wears down. It will need a clean every 6-12 months and another coat of sealer applying. You can do this 2 or 3 times before you'll need to strip it all off and start again.
2) Get proper 2-part entrance matting (rough outside, absorbent inside), because...
3) ...Sand and grit will literally grind the sealer away underfoot - vacuum regularly, preferably with a cylinder vac with floor tool, rather than an upright.
4) Don't use Flash or other high pH floor cleaners (test their under-the-sink floor cleaner with your pH paper!), and definitely not bleach! They need to use a neutral pH cleaner, you can source some really cheap pro products, should only cost you a few quid for 5 litres. I supply every customer with this for "free" (i.e. priced in to job

)
For small domestic areas you should be looking at a couple of hundred quid for about a half-day strip/reseal job, but make the maintenance trips more economical for them otherwise they'll not go for it. My maintenance trips are about 60% of the full whack, providing it hasn't started wearing away.
Don't price too low for Amtico - This stuff costs a bomb to replace, remember!
Any more info needed just gimme a shout
