I've selected several quotes from the masters of the genre that prove instructive to the mystery writer. Bulleted items are the lessons to be learned.
“Death seems to provide the minds of the Anglo-Saxon race with a greater fund of amusement than any other single subject.”
Dorothy L. Sayers
Make sure you kill someone.
“When in doubt, have two guys come through the door with guns.”
Raymond Chandler
Keep it exciting.
“Where there is no imagination there is no horror.”
Arthur Conan Doyle
Use your imagination.
“Even the most ardent readers of detective fiction are not much preoccupied with whether a Colt Magnum revolver or a Bowie knife was used to dispatch the victim. The perpetrator’s purpose, the ‘why’ is what impels them to read on.”
Ruth Rendell
Write the "why" behind the crime.
“The first person you should think of pleasing, in writing a book, is yourself. If you can amuse yourself for the length of time it takes to write a book, the publishers and the readers can and will come later.”
Patricia Highsmith
choose less obvious development and add complications to make the story more intriguing.
“Write what you care about. You can’t construct a book for the marketplace—the nature of the market is to shift constantly—so write about what you love.”
Sara Paretsky
Share your own vision.
“Writing for me is a very physical process as well as an intellectual process. When I've written something that I know is the truth about a character, I can actually feel it in my body... get a sense of excitement right in my solar plexus. I feel it. I know exactly when. It's like a surge of excitement that tells me that's it."
Elizabeth George
Pay attention to your inner voice.
“The best time for planning a book is when you're doing the dishes.”
Agatha Christie
Take advantage of think time.
“I work by trial and error. If I go down one road that doesn't work, I back up. I go down the next road, no, that doesn't work. Or maybe it will work in part and I take a right turn, no that doesn't work. I take a left turn; that might work. So I'm bumbling my way around trying to find the best way to tell a story. Trying to figure out who characters are. Trying to look at the pace, the balance between narrative and description and exposition and dialogue. And pummeling myself with the kinds of questions you have to ask over and over in order to discover what the right answer is.”
Sue Grafton
Experiment.