I disagree on the shoes. Even a cheap pair is much better than going with tennis shoes. Tennis shoes just don't give you the stability you need, and once again you don't need to make the game any harder than it is. Make sure they have at least 7 spikes on each shoe; lots of times they put less on women's shoes.
And the best advice of all; if you can't play well, at least play fast. Nobody minds playing with a beginner who hustles, but nobody wants to play with somebody who lines up every shot like it's the US Open. Be ready when it's your turn.
I was only trying to provide suggestions from the standpoint of not sinking alot of $ when you are just learning. What happens if, after her lessons, she hates golf. *poof* you are out couple hundred bucks, unless you are feeling inclined to try & sell the stuff. Even then you may not get what you paid for them, so you are still out $.
Where do you find cheap golf shoes? I seriously lucked out in scoring my FootJoy's for $10. Had I not, I was prepared to drop $50 or so on a good pair.
I do agree with your last statements about being ready to take your turn & keeping things moving. This would be along those lines as well, if your shot goes completely wrong, don't waste a lot of time searching for the ball. Drop another & chalk up to being a beginner.
Oh and one other thing, be sure to follow proper golf etiquette when out on the course. Fix your divots, remove your tees after you tee off, etc.