I would limit his freedom until he is more trustworthy in the house. Use baby gates to keep him in an area you can watch him, or even attach his leash to your belt loop so he can't be out of your sight. I'm assuming he's still pretty young? I would take him over to the potty pads every hour or so at least, and definitely give him a treat and praise him like crazy when he goes. Don't punish him for going in the wrong spot, but if you catch him in the act I would be very dramatic and screech to interrupt him, then immediately take him to the potty pads and praise/treat if he finishes there.
Hi Hilary, Loki is way too young, a perfect potty trained dog with no accidents and relapses is around 1-2 years old. In my opinion, wee wee pad slows down the potty training process and confuses the pup. If your ultimate goal is for him to go outside, then read and re-read this. Practices makes perfect :)
Thanks guys! Your comments have given me some keen insight. I don't expect him to be perfect, but I certainly want to get him on the right track.
I'll keep on keepin' on. :)