How to develop or improve sensory acuity?

I want to develop and improve my sensory acuity?
What should I do? Is there any exercises I have to do? How to practice them to develop it without anyone knowing what I am doing.
Any video links, books for this?
I think it will make me more perceptive and help me make better understanding with people,right? :)

Is it related to cold reading?
Is good sensory acuity necessary for cold reading?