I've Warren Eckstein (you can Google him or go to
Warren Eckstein - The Pet Show - www.worradionet.com - America's Most Trusted Pet Expert and Pet Humorist) suggests putting a tiny bit of alum powder on poop you find to make it disgusting. It's used in pickling; you can find it in the spice rack.
Although she came from a puppy mill, the fact that you got her that young will give you a much better opportunity to mold so many of her habits as she grows.
Have you worked on the "leave it" command? If you have worked on it with less desirable objects, you should eventually be able to apply it to anything, including poop.
I also taught my puppy "spit it out", and it works wonders (he responded to it when I came up with the idea at about 4 months--it's not too early for yours to potentially understand). "spit it out" was first done with dropping a toy on command and getting an immediate treat and praise. Depending on the object, it can be a life saver.
Do you have a yard? I've heard it recommended that you bury some of her poop right beneath the dirt in the area you want her to go.
You need to be keeping an eye on her as you are so that she doesn't have a chance to make that move. Keeping her on a feeding schedule will also help predict her pooping times.
At this point in her training, you need to remember to throw a big happy poop party, meaning praise her to bits and give treats every single time she does poop outside.
(alty, please correct me if I'm wrong--i love Cesar, but I don't know the method you're referencing. I trust you, and I trust him.) the following is just an idea. If you have intentions of using the clicker in positive obedience training down the road, I wouldn't don't use it before disciplining her. A can or a tums bottle with some pennies is a good distracting noise maker.