
Everything Val said! Do try and look round any potential school though. I started a month-long course at a school in Scotland (I won't name it in case that's not allowed, btu I don't think there are many up there!!), and ni the end I was only there for a week: the groomer training me and 4 other people (1 left by the end of that first week) was very brusque, certainly not a people person; she would readily criticise me but not praise correct work much. I also remember a particular incident when she had a go at me for using blunt scissors (which she gave me), only to give me a better pair - which were also blunt. I also had to be sure to ask what shampoo to use - she woudl jsut say "it can go in the bath now" with no further instruction, beyond 5 minutes on the first day on how the shower worked.
The parlour itself was unpleasant - a constant smell of pee, not helped by a very cramped, humid environment. The dogs waiting for grooming were kept in small cages with no water, and you can imagine the noise. Also, she was not nice to dogs that didn't behave - the one that sticks in my mind was a toy poodle. Nasty little dog anyway, but I lsot my temper with it - shouldn't have, my bad, I know - and tapped it with a brush; she called me on that, fair enough. But later in the grooming, she came over to it to show me something and when it started to struggle around and try and nip, she - literally - picked it up by the *neck* and shook it. Not nice.
Okay, that got longer than it should have! But, all I'm trying to say, is do check out any school thoroughly. As it was, one of the other "trainees" was actually a professional groomer from my own county who wanted to see if there were any other techniques that could help improve her work; she left first, but not before giving me her card, and in the end she taught me to groom properly in a clean, airy parlour with very well-behaved dogs and a wonderful atmosphere, and friendly staff. If only I'd known she existed, I'd have gone there in the first place! Sadly she's miles from you or I'd recommend her!
Oh, one last thing - I consider impeccable patience to be the cornerstone of a good grooming business; chances are there will be some dogs that will take some time to get used to you and allow you to groom them without making too much protest. Most are okay IME, but there the odd one or two.