Housetraining a puppy isn't usually a short process. I'd also suggest, that with a dog that's going to be the size of a GSD/Chow mix, you'll probably want to train him to use the outdoors rather than a paper.
Restrict his food and water intake - none after 7:00 p.m. or so. After he's eaten, let him have a short quiet time, about 15 minutes or so, then play with him - either inside or out, although I'd suggest starting inside then going out. That should stimulate his system to 'go.' If the weather's okay and he's having a good time, let him play outside for a few minutes after he does his business so he doesn't get the idea that once he's done it the fun's over.
Take him out every two or three hours, whether he acts like he needs to go or not. Play with him; if he's got to go at all, that should get things accomplished.
And, most importantly: Praise him to the skies, pet him, make a huge deal out of it every single time he goes where he's supposed to.