Here is some good advice on the craft of manuscript editing. Vonda McIntyre has this (pdf) good introduction to manuscript preparation. Or, in a nut shell, use 12 point courier font, double spaced lines, with Title / Author / Page in the upper right corner, one inch margins on all sides, printed only on one side. Oh yes, paragraphs are indicated by first line being indented and don’t use italics, use a single line underscore instead. Bold has a squiggly line underscore.
More of my links on manuscripts at del.icio.us.