First, download Mitsu's soundpack for his custom sounds package. Check the "Sounds" forum for the URL for the newest package. Fly the Spit IX and the Spit V so you can recognize their sound signatures. At the merge, you'll need to know whether you're fighting against a IX or a V, since each model has different strengths and weaknesses (ie, you won't outturn a Spit V and may not be able to outrun a Spit IX).
Second, surf the web for some additional sounds for the Mustangs. Mitsu uses the same sound for the Spit IX as he does for the P-51B and the P-51D, which is historically accurate but I prefer to know if the plane diving down on me is a Spitfire, B-stang, or D-stang, because each one is different from the other. One resource is
http://www.simviation.com for some of the MS FS and CFS engine sounds, which can be used in AH, too. You can use just about any .wav file, including some of the samples of car and boat engines if you want.
Third, turn down your engine sound so that you can still hear it but it doesn't drown out the outside sounds. I need to be able to hear my engine so I know if I'm on WEP or not and what my throttle setting is during combat without looking at my dash (since I'll be busy looking at the enemy). Some folks prefer to fly in silence, but I don't.
Next, download some of the custom gunsights from the AH "Downloads" section. I also made a custom gunsight but haven't gotten around to loading it up there - shoot an email to
nascargofaster@yahoo.com and I'll send it to you.
Raise your seat in the cockpit until the gunsight crosshair is almost off the screen. No matter now high you raise the seat, the guns will converge at that point in the crosshair, but I prefer to keep some of the horizontal reference line in sight.
That should be enough to get you started. Good luck!