I would make sure when you are not home, you gate him into the kitchen with the pads. At least then, if he misses, it's easier to clean up! And he won't get used to using the carpet for his "area".
I know that some have had success with tethering the pup to themselves when in the house, so that he can't sneak off & go when u r not looking!
Just attach his leash to his collar, and the other end to your belt.
And take him outside (or wherever it is you want him to go) VERY frequently (once an hour if possible, every 2 hours at the longest). When he does go where u want him to - make sure you make it a BIG party. Lots of praise (and/or treats). Those are my tips, but I am sure you will get lots of great (better) information from others here.
GOOD LUCK!!!!!