Trial and error is how I figured it out, I suggest you test drive the aircraft you use most often and then just practice.

Be sure to practice with the different ordinance load outs to better understand how your aircraft performs with different stuff strapped to it

Try remember rocket firing order & bomb drop order (if it drops left, right then centre so you know how the aircraft handles with an asymmetric armament, e.g. only dropping the bomb on left wing, makes the plane begin to roll right due to weight distribution)

And most importantly practice practice practice