It may seem like an impossible task to boil your book down to 140 characters. But fret not. It's easier than you think, and it comes in handy when all those twitter pitch contests roll around.
For starters, check out this great How-To article by Carly Watters of PS Literary. A
My own method went like this:
I took the pitch portion of my query (the "meat" of the story, minus the bio/intro stuff). I then cut, cut, cut, cut, getting rid of all the extraneous details, focusing mainly on important plot points, until I had a polished, shorter pitch. Say, about 50 words. I kept that in a separate file for future use. (Some contests will ask for pitches of different sizes, so it's good to have a variety stockpiled.) I then cut that 50-word pitch down to one or two sentences, making sure the conflict and stakes are obvious. (Also, saved that one for future use.) Then, I took my 1-2 sentence pitch and cut out all extraneous words and unnecessary junk (you won't believe what becomes unnecessary when you are desperate to fit only 140-characters). Again, make sure the core stakes/conflict is there.
By way of example, this is the twitter pitch that interested my agent in #PitMad:
Cass forgave her BFF for stealing her forever crush. But an impulsive kiss makes stealing him back an unforgivable possibility.