Holmes sees his new acquaintance's symptoms of tropics, sickness, and injury, and is able to see how they fit together and offhand claim: "You have been in Afghanistan, I perceive."

When Holmes famously quips that the solution of a case is "elementary," he's not simply dismissing the detective work as easy. Rather, he's talking about elements, the essentials of a situation.

"Whatever the specific issue, you must define and formulate it in your mind as specifically as possible — and then you must fill it in with past experience and present observation," -- Konnikova writes

In the novel " Hound of the Baskervilles," Holmes assembles clues not just by reading everything he can find, but involving all his senses.

We shouldn't neglect our senses — since they influence our decisions in ways we don't even realize.

Konnikova's take: "Holmes ... focuses all of his faculties on the subject of observation ... He listens, as is his habit, 'with closed eyes and fingertips together.' ... He will not be distracted by any other task. As passive observers, we are not doing anything else; we are focused on observing."

When Holmes is dealing with a particularly thorny case, he occupies himself with another activity, like playing the violin or smoking a pipe.

Konnikova contends that pipe smoking is a way for Holmes to constructively distract himself from his thinking. 

Holmes talks to Watson about everything.

The telling helps, Holmes says. "Nothing clears up a case so much as stating it to another person."

When Holmes meets a would-be source of information, he profiles him or her, looking for any advantage that might be communicated by their appearance.

He tells Watson how he nabbed details from a gambling type from intentionally losing a bet to him.

If you're out there detecting all the time, you need to give yourself breaks.

Watson, who writes of his friend: "I knew that seclusion and solitude were very necessary for my friend in those hours of intense mental concentration during which he weighed every particle of evidence, constructed alternative theories, balanced one against the other, and made up his mind as to which points were essential and which immaterial."

Here's what he said when Watson begged him to eat:

"The faculties become refined when you starve them ... surely, my dear Watson, you must admit that what your digestion gains in the way of blood supply is so much lost to the brain. I am a brain, Watson. The rest of me is a mere appendix. Therefore, it is the brain I must consider."