How to: Chess Opening Study

I see these threads pop up all the time and while I'm no expert at all on openings (I have maybe four or five variations committed to memory about six or seven moves deep) I think I can make a reasonable explanation of a good way to learn and assimilate opening moves and ideas.

Looking over openings in books is definitely beneficial, but if you never learn why the moves are being played (and often it's explained) then you are never actually going to learn the opening (though you may memorize a variation or two).

For example, I played a game against my very strong chess computer the other day, I had the white pieces and opened with E4, the computer played the Caro Kann defense. Now in my ignorance I looked back to 'Understanding the Chess Openings' and what it said about the Caro Kann advanced variation, I recalled that the G4 pawn push was important to make time on the bishop... however...

Badump.