The other game with "Sky" in the title. [Zelda]

[KentaRawr!]

If you're new to motion controls it's definitely going to feel weird. My friends were trying to swing their arms super wildly when they first played. The best thing you can do is try to be as lazy as you possibly can. If you put in too much effort you'll tire yourself out, and your larger motion is more likely to be inaccurate. So find a good way to sit, and try to keep the controller as close to your lap as you can, in a relaxing way. At least, that's how I do it. It makes combat so much easier.

Edit: Oh, and the diving part shouldn't be that hard, at least not from what I remember. :O Imagine that Link himself is the remote there. So if your controller is perfectly level, Link will fly straight down, because he's level. Tilt it forward so Link'll tilt forward and whatnot.