There are few things more embarrassing than looking back on things that you've made in the past (read: blog posts. Gah!). When you're just starting to crochet, and you're out there floundering around by yourself, odds are no one will think to tell you about the right and wrong sides of crochet. I'm not saying that crocheteers are mean, or just sitting in their love seats, anxiously awaiting your next mistake so they can snicker at you. It's just a skill that once learned, you don't think about.
So basically, when you crochet in a round the two sides of the piece have different textures.
The 'right' side looks like little 'v's.
When you are stuffing a piece, you'll want this side to be facing out.
This penguin I made two nights ago has the right side facing out.
You can see that the stitches arrange into rows.
The 'wrong' side is much bumpier, and isn't as tidy looking. This is the side you'll want to be facing in.
This bear is the first amigurumi I ever made. Naturally, he is inside out.
You can see that the stitches on this side arrange into columns.
So that's it! By using the right side, your amigurumi will look much more professional.