Congrats on your new rudder pedals. I've been using the non-Pro CH Pedals for over 10 years now. The two pedals are set much too close to each other, but aside from that they work so well I've never replaced them.
The best thing you can do is practice a LOT making coordinated turns where combat is not an issue. Obviously, you don't want your head buried in a cockpit during a dogfight monitoring your slip 'n yaw gauge. A coordinated turn is the most efficient way to TIGHTEN your turn, plus it ensures your bullets are going in the direction of your travel -- which is what you want when peering through your gunsight.
You can also use your rudder pedals to introduce deliberate yaw. This can throw off an enemy's attack run if you're travelling in a slightly different direction to where your nose is pointing. (Well, in theory, at least. In practice? Relying on this trick in CoD will probably get you DEAD! LOL) .You can sideslip beautifully in CoD if you need to lose altitude quickly without picking up speed -- very handy when landing your aircraft in a combat zone and you can't spend a lot of time on a nice, long, slow landing appoach. Also, your new pedals are invaluable when strafing gound targets in making fine adjustments to your bullets' point of impact as you rapidly approach your target.
You have many reasons now to thank your very lovely girlfriend for such a thoughtful and useful gift!
