Once again, this is a somewhat optional step, but one that i find results in a piece of stranded colourwork lying flatter, looking more even, and altogether just being satisfying on a fundamental personal level.
First, wash your work and squeeze most of the water out of it. I like to jelly roll my work in a towel, and step on the roll to press most of the water out, but do what works for you. The goal is to have a piece that is damp, but not soaking, on a dry towel that's covering a hard surface like a table.
Finally, dear knitter, this is your weapon:
There is no delicate way to put this: you are now going to beat your knitting into shape.[1] I prefer to do this by putting the right side of the work down on the table (work is inside out), but either way will work. Apply even pressure with the flat of the spoon, and make sure to shift the tube around so that you don't accidentally create seams at the sides. While doing this, you'll find that you can shape the work a bit...if you have any uneven edges or bits you'd like to adjust, give them some extra attention until the work looks blocked and even. For the puppy sweater, this took me about five minutes of fairly steady drumming, a larger project would of course take longer.
At the end of the process you should find that the work is noticeably flatter and the stitches more even, much as when blocked a work is "nicer" and more even.
1. I am sure that there is a really interesting back story to how this technique was created, but it is one that I came across some time ago, and I unfortunately don't know the origins. I like to imagine, however, that it was the result of a very overwhelmed knitter taking their frustrations out on a piece of particularly difficult stranded knitting, who either decided that they liked the results, or who came up with "it makes it look nicer" as an alternative to owning up to their violent tendencies to worried family members.