Since it's not my story, I won't talk about his story idea at all, but I want to type out what I told him about putting together a synopsis, mostly for my own reference. My agent and editor will want a synopsis of Man Bites World soon, and it will be helpful to have all this in a place I can review it easily.
So here are my ideas about writing a synopsis for a plot- and character-oriented, single protagonist story. Tell me where you think I'm wrong or taking the wrong path. I encourage informed correction.
First, he was planning to make the synopsis three pages. I told him to cut it to a page and a half. The half page should come first, with the name and title taking up the top half of the front page. The fewer words, the smaller the chance the reader will hit something they don't like.
Now, all synopses are essentially a recitation of plot events, but which to include and which to cut? And more important, how to tie all those disparate events together.
The first thing I try to do is decide what the protagonist's character arc is going to be. Where do they start? How are they changed? What happens to them at the mid-point that marks that change? I told Director to include a sentence in the first paragraph plotting where the protag is, one sentence in the last paragraph acknowledging where they end up, and one near the top of the page two that demonstrates the way the character is being forced to change.
If the plot events still seem to disparate and don't add up to a coherent plot, I told him to try rephrasing all the story beats to make them relate to the protagonist. Not "Eileen and Joe elope," but "Karl is heart-broken when he finds out that Eileen and Joe have eloped."
One thing I encouraged him to do was to have multiple antagonists, some more dangerous than others, but all with different goals (if possible). He was headed in that direction anyway, but I wanted to make him think about it explicitly. Here's how that ties into writing a synopsis, especially the super-short one I recommended to him?
Well, one of the problems with any synopsis is knowing what to cut and what to leave out. I told him that anytime the major characters change goals--the protagonist decides to save the village rather than attack the overlord, the creepy co-worker goes from stalking the heroine to sabotaging her wedding, the disturbed family man goes from building mashed potato sculptures to rushing off to Devil's Table--that needs to be in the synopsis. That change and the stimulus that prompts it.
Next I told him to try to use words that reflect the tone of the finished piece, but his eyes started to glaze over, so I skipped it.
And then I told him to send it to me, because writers can't always tell when they're being appropriately vague or putting in a little string of details that spurs the reader to think all the wrong things. And Director isn't a writer.
That's what I try to do, anyway.