I've written arrangements for choirs and strings in the past, but I usually write music with my voice or a keyboard and then I'll get someone who is good at writing scores to write it out. Or, if I have the luxury of time, I will go in a room and hear the people perform and then change it through what I hear, not on paper. I can read music OK, but I probably rebelled a little - music changes into something else when you read it.
