I’ve tried searching this out - but have only gotten a bit more confused!
I have a duet for saxophone and drum set. I want to add an occasional cue staff to both parts, giving essential rhythmic (or perhaps pitched - in the case of the sax) cues where necessary, and then disappearing. Obviously I don’t want these extra staves to appear in the score - only the part. I wasn’t certain if the approach is to just add and take away extra staves, or to give each of my players the other instrument, and then send cues to the extra staves… I’d be grateful if someone could lay out the procedure for me!