Editing, formatting, typesetting, engraving, proofreading... anything to do with the score that the performers see. I've worked on a wide variety of scores and projects in various roles, from collaborating with the composer on notation decisions and style of presentation, to proofreading for another editor. In each project it's all about finding the best way to communicate with the performer - and it isn't just about the notes and the stave, but every presentation decision that you make can inform the approach a performer takes to the piece. Of course, sometimes you just need parts making quickly and accurately, but sometimes you need someone to think about how wide a wiggly line should be, or how to pace the page turns to reflect the energy in the music. Details are so important.
I might be the person for you!
I work in both Dorico and Sibelius and whether you need someone to quickly format a set of parts, transcribe handwritten notation, or just give a second opinion on how to present something, email me at fraz [dot] ireland [at] gmail [dot] com to discuss your project.