[dubiousdrift]

traz, nice post!
One of the first board reading exercises that I did when I first started learning was to take two cards and a flop, then name all the hands that beat those two cards (similar to Ed Miller's 'Hidden Outs' exercises). While this was a great exercise and a real eye-opener that helps to tighten down a noob's pre-flop range, it also plants the 'monster under every bed' neurosis seed (or it did for me anyway). This commonly led to my misunderstanding of range as "the specific hands that beat me, one of which is sure to be in my opponent's hand"

Some of the things that I think of when I'm trying to put a person on a range now include:
1) Does this player play junk hands? Loose players who see 80% of flops *must* be playing all sorts of garbage including stuff like J3s - it's sooted, 95o - i could make a straight with it, K9o - I'm not dominated often enough for it to matter (or even better - what do you mean dominated).

2) Is the person aware of position, and do they play it. If so, what position are they in this hand. If not, no adjustments are necessary to widen the range for later positions. The person who routinely limps from the first three spots has no idea what position is.

3) Does the person limp a lot of hands, and only raise pre-flop occasionally? If they raised pre-flop, they probably don't have a set of 7's, but if you have a set of 7's, you can probably stack them on a A,K, or Q high flop.

Angel Largay's book contained a great collection of caricatures for various players of varying looseness and aggressiveness. Even if you don't agree with his strategies (opinions are varied here on 2+2), I think the psychology section is worth the price of the book - and it helps to be able assign people around the table an archetype of 'former football star', 'curmudgeon', 'the wife is shopping and we are trying to out-spend each other'.

Mostly however, I think this is a slowly acquired skill and that the more I actively observe, pay attention and devote 'effortful study' to putting people on ranges, the better I get - But I still have much road to cover.