I read a LOT of synopses submitted by writers to my publisher, and they're almost never interesting. That isn't any comment on the worth of the books summarized by the synopses, which span the spectrum from great to okay. Rather it's the nature of their synopses-- they are so often just chronicles of what happened. "This happened and then that happened."
"But isn't that what a synopsis is?" a writer might ask. "A chronicle of what happens?"
No. A synopsis is a brief presentation of the story. The story is more than the plot. The story includes character, theme, emotion, conflict, change. So maybe we should think more about that as we start a synopsis, and less about what events we're going to summarize.
But just to get really practical here-- one thing I'd suggest that doesn't require a full re-invention of the synopsis is... make use of the first sentence of the paragraph. Often the paragraph starts with an event or character action.
Jack gets a ticket and goes to her concert.
The murderer strikes again, kidnapping a mob accountant and leaving his torn body by the roadside diner.
Trouble is, that can lead to a jagged read, and a seeming reliance on event rather than conflict or emotion.
So think about using the first sentence as a transition from the previous paragraph's action. The transition can be time ("Three days later" or "After that") or cause/effect (reaction rather than action-- When Jack reads that Sally is singing at the local stadium, he knows he has to go) or emotion (Jack has never gotten over Sally's betrayal) or conflict (He still had enough blackmail material to capture Sally's attention). Then have the event or action, and its effects and how it changes the story or emotional arc or character.
That first sentence in the paragraph eases into the new event as a transition from the old, making for a smoother flow. But also an emotion or conflict line there can keep the synopsis focused on the experience of the story and not just the events.
So next time you write or revise a synopsis, try putting something in front of the "event" at the start of a paragraph, transition, emotion, or conflict (or all three). Just try it, and report back!