I find that my most productive editing is done by hand--sitting with a printed copy in front of me and a pen in my hand. I don't know if this'll always be true, since it used to be the only way that I drafted material, and that isn't exactly the case anymore. Either way, I've got my own pen-and-paper standards that I typically use to speed up working through the text (which can take anywhere from 5 to 20 minutes per page, depending on the changes).
First off, I always print double-spaced with 1 inch margins all around. I write relatively small, so this means I can revise sentences in the blank line above them. The top, bottom and sides allow for larger edits too. I print duplex (love my "new" printer that my wife convinced me to buy), so I don't have blank sides to use.
Removing text is almost always demarcated by parentheses and a straight line through. If it's a whole paragraph (which of course never happens :P ) then I'll just cross-hatch through it. Single letters, often for tense changes, can be done with a slash through (/).
Inserted text normally gets written immediately above where it's going. If things are getting a little cramped, then a simple ^ beneath takes care of the placement issue most of the time.
I write a paragraph mark something like an R with two vertical lines--don't know if that's standard, but that's what I do. If I need to remove indentation (i.e. scoot two paragraphs together) I write an arrow like <=.
I've got a variety of abbreviations that I use commonly. w/ for with, w/o for without, single capital letters for primary characters (if their name is longer than four or five letters at least).
Can't think of much else at the moment, but that's how I do it. Next time... moving from ink to bytes.
Word Delta: +105 words over ~10 pages of edits. Leaner, meaner and more descriptive!