Dorothy Parshall, two tips with Apple helplines:
1) Find the time when the best techies for your purpose are online. Here in Ireland that's around 9am to 10am our time, when the helpers tend to be Irish or Scottish and reliably tech but (usually) able to explain without patronising. I've had some spectacular good luck with Arabs and Indians too, mind!
2) Always give the agent your phone number first thing, so they can call you back if the call drops.

And in general talking to helplines, I find it's better if I ask the person their name and write it down - doesn't matter whether they're using their real name or not - and use it in conversation the way I would with anyone else I'm talking to. "So, John, I need to press the little button at the bottom - the 'home' button, is it?" sounds much better, and makes both sides feel human. If apps are restarting or anything and there's a bit of a pause, it's nice to say "Where are you? Oh, X place? What's the weather like there today?" etc - human conversation.