I’ll tell you what I tell my students. You have to treat it like you’re in the kitchen creating something delicious for the ears. The key to creating Digital Audio Awesomeness is, your script interpretation, sound f/x usage, music bed selection and volume levels.
You want to make sure you “sell” your read to its fullest potential and make sure the music bed “fits” and is appropriate. You wouldn’t want to use Slayer for a Day Care Spot or One Direction for a UFC Fight Promo, right?
You’ve got your main ingredients, the “copy” (script) and the “bed” (music). It would be pretty bland to put just those two together, so now you have to spice it up a little bit with sound f/x. Too many f/x or varying audio levels and it becomes “noisy”. Same goes the other way, not enough f/x and it’s too bland. Like any other recipe… with time, trial and error, you’ll get the taste “just right”.