Well what I do is look at real images of the animal you're planning on drawing to get an idea of the general shape. And instead of doing the :3 kind of mouth, stick with more smooth, less chibi lines. For example, in this picture http://farm1.static.flickr.com/56/1.....22e8ea2e9c.jpg Notice how it doesn't have an exaggerated maw as you see in things like this :3 It's more of a straight, fluid line that dips up in the middle slightly. Hope that helps!

http://www.furaffinity.net/user/the.....rryartacademy/ might have some stuff you might find helpful