I was feeling overwhelmed by the size of the task facing me in doing some fairly major rewriting of my novel, A Greater World. I'd make some changes only to discover I'd already written something similar elsewhere and I kept finding repetitions. I wanted to explore how the romance between two of the characters built and developed and it's really hard to do some of this retrospectively.
Solution - my giant spreadsheet. I actually LOATHE Excel and normally avoid it like the plague - but it actually proved to be a big help here. I made a series of headings - the scene - the main plot point - his thoughts - her thoughts - key quotes to support them - physical contact etc. Then I cut and pasted my way through all the scenes they shared until I had it all captured. Next I used some coloured pens to highlight areas so I could see the pattern of the relationship emerging. Once I had it all I was able to add comments, Post-Its etc and then use it to steer the editing. Piece of cake!
You could do something similar with Post-Its only - but I found cutting and pasting from the manuscript made the job much easier. The hardest bit was sticking all the spreadsheet pages together and working out where they went. A Greater World is written using Word - and I now use Scrivener which has the Cork Board feature and virtual index cards to facilitate this process.