Should You Correct A Puppy With A Pinch Collar?

Hi, Adam!
My husband and I recently purchased a white German Shepherd. She is 12 weeks old today and quite a handful. Sometimes she can be so sweet, but other times she is actually quite vicious.
Well, I don't know if vicious is the right word, but when I tell her "No!" she just gets more agitated and lunges at me with her teeth bared.
I got a small pinch collar since she's a puppy but I have a question as to how it should fit. When I take 2 prongs out it is snug against her neck and I worry about it being too tight. When I only take 1 prong out, it sort of slides down her neck a little bit and she constantly scratches at it and it circles around her neck and doesn't stay put. Which is the right fit?
She is really a handful and I think the pinch colla View the rest of this article