Eggs – Pasteurize egg yolks

The best thing I've figured out about turning eggs is: do not do it too early. You need to wait for the cooked part of the egg to develop a strong texture before it will support its own weight. It's very difficult to turn a floppy, soft egg, where it's comparatively easy to flip an egg that has been cooked more completely on one side. I also use a relatively high heat, as this "crisps" the cooked surface. It also makes the egg more attractive.

The spatula you use can make a difference, also, though I believe this is minor. The spatula you want is a plastic one with a relatively thin, flexible blade. The really heavy spatulas tend to be too tall, in my experience, and push the egg rather than sneak under it.

No, it doesn't have to thicken, at least not in the way custards like creme caramel thicken. "Coat the back of the spoon" is just a misnomer, a term known to experienced cooks which confuses everybody who learns to cook on their own.

For "Coat the back of the spoon", read the comment riotburn left at the question What is the correct consistency of a cream soup?. It says: "The best way to describe 'coat the back of a spoon' is where if you dipped the spoon into the soup, take it out and holder over the pot, you'll find thin film (<1mm thick)."

For the ice cream, heat to between 80 and 85°C. I've explained it somewhere else, but in short, this gives you enough thickening without overcooking. If it is really gelato and not French style, it should be thickened with starch anyway. Also, watch videos on the Internet for how to make ice cream, they show the correct consistency. I think Allrecipes had a good one, but their search is so strange, I can't find it and don't know if they have it or not.