We have poodles, toy poodles to be exact, so it's important that the little guys (and girls) and warm enough. Since it routinely gets to forty below in the winter, "warm enough" is a relative term. Still, we have to try, so this time every year I break out the fleece and get to work.
If you want to make a dog sweater (or a cat sweater) yourself, it's actually not all that hard. You don't even need a pattern, though patterns for pet sweaters can be found at most fabric stores. At home, however, I don't bother with a pattern. I simply get out the fabric I'm looking for and have the dog (or cat) in question lie still on the flat fabric. I can then trace the pet, making sure to leave enough ease so the sweater fits when I'm finished. I even add a hood, though since the animals hate hoods, this step is only for my own entertainment.
Once I have two pieces cut (because all pets have two sides, let's remember), The rest is easy. Sew it all together, making sure to leave enough room in the belly to get the sweater on the dog (I don't do Velcro or elastic for pet sweaters because the cat eats both).
I really wish I had a picture of one of the cats in a sweater, but they seem camera shy. Or maybe they're embarrassed. I did use pink bunny fleece for both of them...and they're boys.