I would introduce both the peepad and outdoor training at the same time. First, talk to the breeder and find out if she's done any housetraining already. You may find some of the work has already been done for you! If not, try this: When you have her in a playpen while unsupervised, with a crate she can sleep in, start by covering all of the floor, to the edges of the playpen, in peepads. Then, no matter where she goes, she's using the "right" spot. If you see her using the peepad, throw a little puppy party, pet and play with her and give her some tiny, tasty treats (though wait until she finishes, or you may cut her off 'midstream'
). When you have her out with you, pick up all mats and area rugs off the floor, as to a learning puppy, pee pads and small rugs can seem VERY similar. Young pups usually need to pee or poop every couple hours or so, so about an hour after you took her out of her playpen, ask if she wants to go out and then carry her outside. Reward and treat her if she potties.
After a couple days, begin to slowly remove a few peepads from the playpen. Start by removing the ones closest to her crate, first. A couple days later, remove the ones that line the edge of the playpen. A couple days later, remove half of whatever # of peepads are left. Just keep doing this until there is only 1 peepad remaining in her pen. Go slowly at first, and watch to make sure she's still aiming for the pads and choosing them over the exposed floor. If you go too quickly and find you need to backtrack a step, that's okay. Keep rewarding her each time she does it right, and every time she's outside of her pen, reward her when you take her outdoors to potty.
When she's using her peepad in her pen every time, place a peedpad down when she's out with you, too, and reward her for using it. Also continue to take her out and reward her for outdoor potties. When she's using both the pads and outdoors reliably, start to put your area rugs back down and WATCH HER LIKE A HAWK. She is going to try to pee on those rugs. As soon as you see her start to squat on one, clap your hands, get her attention and place her gently on her peepad. When she uses it, reward as usual.
The real key to successful housebreaking is to make it as difficult as possible for your puppy to get it wrong!