Muzzy's GunQuest(tm): A history of a noob trying to figure out how to shoot.
1. In offline mode, with tracers on, take deflection shots at the drones (coming in at angles while turning). You will discover that the bullets will curve and drop in ridiculous amounts. Solution: Unload G. That is, straighten out, fire ahead of the target and let it fly into your guns. Shooting while pulling g's is very very difficult.
2. In the TA: Up a 6x .50 caliber plane. Set the convergence at 400. In radio: type .target 400. A range target will appear due north of your plane. Hit autopilot and shoot. Zoom in (hit z) and look at where the bullets have landed. now type .target 200. Pick a clean spot on the target to aim at and fire again. The bullets might be landing differently this time. Try it at 500. Now do this exercise with your favorite aircraft. Try different convergence settings. If you have a mix of guns, fire one type first, then the second. You'll see that the bullets will sometimes land higher or lower than your aiming point, or they may look scattered. Try and keep this information in mind while in combat and fire accordingly.
3. In the TA: hit ctrl Tab, activating the lead target sight. Close on a willing training partner and use the tab key to lock the sight on him. Note how much lead you really need to pull to hit a turning target. Practice shooting each other with the lead gunsight.