I know that with Lexi..she really needed to know that peeing inside is bad! So I would make sure that when i caught her peeing, I would very firmly say NO!

or Clap really loudly. (I read that you need to interupt them, then bring them to where they should go). And obvisouly taking her out often enough that she wouldnt' pee indoors. TONS of praise when she did pee and poop outdoors. In no time she was peeing outdoors only. She will randomly have accidents, but thats usually when she may be under the weather. I am now working with my new pup Nico...and yes its tough, but he is doing great with going outside, and when indoors, if I cannot watch him, he goes in his ex-pen with Lexi and i have pee pads set up, and he uses those very well. I hope this helps!!