We'll put his arms resting casually at his sides ^^ He looks happy! The elbow should be at about belly-button level - that little spot where the waist tucks in a little (or pops out ^^ ) When standing, the hands should reach mid-thigh. Because he's sitting with his knees up, his hand-paws will rest on his knees.
Now of all the parts that are hard to draw, paws have it... I spent two months once drawing nothing but hands, and I still have trouble with them. Make them a little thicker than human fingers. The claws (if you want to draw them. On something like a rabbit or squirrel you might not want to) are about the same placement as nails on human fingers. They're diamond-shaped from the front, and triangle-shaped from the side.
Okay! Now we can start going over the pencil lines with a pen (or my prefference, a fine-point Sharpie). Now in all of our stages we've been drawing with light lines. They don't have to be exact, because the lines we want we'll go over with the sharpie. This is where we put the last of the detail like the fuzz on the top of the head, and on the side of the face ^^