I'm not sure how saying three words over and over again with different inflections "breathes life" into a character, but that's what Vin Diesel talks about doing in the Guardians of the Galaxy clip above.
As a little extra bonus, and I do mean little, check out two new outtake clips from the movie below. Also, make sure you check out some of the other tidbits found in the upcoming home release of the movie over here, including an extra second or two from the upcoming Avengers flick.