You can learn so much about attention to detail from reading Sherlock Holmes novels and short stories. Scientific America has a lesson from Holmes about paying attention to what is not there:
When Inspector Gregory asks, “Is there any point to which you would wish to draw my attention?” Holmes responds, “To the curious incident of the dog in the night-time.” But, protests the inspector, “The dog did nothing in the night-time.” To which Holmes delivers the punch line: “That was the curious incident.”
For Holmes, the absence of barking is the turning point of the case: the dog must have known the intruder. Otherwise, he would have made a fuss.