Pipe-smoking is a skill like riding a bicycle. You will have to focus on it at first, and then it will become unconscious repetitive habit, and finally it will transition to second nature where you will “feel” the pipe as an extension of yourself.
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Most literature refers to smoking a pipe as “puffing” or even “sipping,” but neither of these are really accurate. A pipe smoker regulates the air flow through the pipe by using capillary action. The mouth clamped around the bit of the pipe seals that end of the tube, creating a slow but constant pressure toward which air is drawn through the bowl. This enables smoke to slowly fill the mouth and circulate around the areas where it is absorbed, mostly the roof of the mouth and tongue, and keeps temperature in the pipe low so that more flavor is conveyed.
http://www.deathmetal.org/lifestyle/introduction-to-pipe-smoking-and-pipe-tobacco/