Music engraving is an art more than a science. Digital engraving using computer software has automated many aspects of the engraver's work, but creating beautiful and easy-to-read musical material is still a matter of engraving skill.
Here are three examples of my work as an engraver. Click on the images to open PDF versions of the sample pages. If these display on the screen badly, please print them to get a better idea of the finished product (although only laser printing to high-quality paper will approach publication quality).

This is a page from Chopin's Nocturne Op.15 No.2. From the engraver's point of view it is a typical romantic piano piece, full of interesting problems to be solved. Look particularly at the right hand part from bar 25, where Chopin's notation strives to show several internal lines at once.
One page of a choral work by Julian Anderson called Beautiful Valley of Eden which I engraved for Faber Music. Each section of the choir has its own time signature and tempo, with the coordination between the groups shown by the heavy arrows.
A page from Ophelia's Last Dance, by Oliver Knussen, which I engraved in 2011, again for Faber Music. One can see the distinctive engraving preferences of the composer in this sample, with large centred time signatures and non-standard beaming to show musical connections, and so forth.