I'vw composed a piece of music that contains various sound effects, most notably movie trailer-style "braaaam" horn sounds, and large, synthetic drum hits that don't fall within the drum part. For the purpose of my qualification I have to write a full traditional score for this, and I couldn't find anything about a convention for how to notate sound effects like this on a score.
Is there an existing convention for how to notate sounds like these on a score, or any ideas on good ways to do it? These can't really be notated in with the horn or drum parts as they're completely distinct from those musical parts.