It was my first venture composing/orchestrating and had very little knowledge of what would work. But I wrote a few passages for string quartet and begged for volunteers from a student orchestra class. I gather them in an empty classroom with my Sony stereo tape deck (this was in the early 70's). They were in a hurry so they wouldn't miss dinner at the dorm. With one rehearsal for each segment I got the job done. It's pretty raw and shaky but I to this day enjoy the result as crude as it seems to the average ear. I hear a successful moment in my adventure.
Since those good-old days and the development of sequencing and sound modules I've composed from string quartets to full orchestra. One of my favorites is a a piano trio that is sequenced with flute doing the violin part and clarinet doing the cello for clarity. Take a listen to the 2nd movement and follow along in a PDF version of the score.