I remember reading some great advice on this a couple of years ago on author Nalini Singh's website. At the time I was nowhere near having a completed manuscript, but of course I spent countless hours trawling writing how-to websites and reading the writing tips on author websites hoping for insight into things I wasn't vaguely ready for yet. Sound familiar?
Anyway, fast forward to the present, and I'm actually in the position of needing to revise my manuscript. Not, sadly, at the request of a publisher who has just bought my book. (Fingers still crossed on that front). But at the request of my agent.
I've now had the chance to road-test Nalini's suggestions, and they've worked pretty well for me.
Basically, she suggests that you start with the easy stuff and work your way through to the hard. Having analysed the revisions I need to do, if I'm honest, I have to admit they all fall into the easy category. No character motivations to change, or subplots to delete. And no major changes to storyline. All I really have to do is add more scenes to my ending, as well as which my final (fairly short) scene has to be cut or heavily revised. That doesn't mean I'm looking forward to doing it, but it's certainly achievable.
Anyway - I decided to tackle the shorter changes first, then move on to the longer ones. Shorter and longer in terms of amount of writing needed. Most of the short changes are to add in foreshadowing to build towards a climactic event I'm adding to the ending - and I've now completed them. Kind of like weaving some extra threads into a completed tapestry.
Next comes the fun part - adding a few whole scenes, and deciding what to show and what to skip over, which is never easy. I'll let you know how I go. And it will be interesting to see how many words this adds to the total length of the MS. I really have no idea at the moment.
You can read Nalini's suggestions for revisions in full here. If I do have more comprehensive revisions requested in the future I'll be keeping her advice in mind!