It is hard to find practical guides to doing anything magical. Magicians don't like to reveal where to place the hinges or what to feed your pet dove. So I like it when an article gives away the secrets, like this one: Charles Finch: "Writing Great Mystery Plots"

Here's the kernel:

I start by writing a brief, extremely dull short story ...about three pages ... I refine it for weeks...

that small story contains a full, straightforward account of the case my detective must solve, told in simple English. It enumerates who committed the crime and why, how they covered it up, and all the stuff of mystery novels: clues, red herrings, false leads, bloody knives, mysterious scars, anonymous notes, midnight rendezvous

in short, all the details I know I’ll have to omit from the real book I write, the actual mystery novel.