Lets say that I have a plane and a reference plane separated by some distance. Each plane has a sketch in it. Does not matter what the shapes are but lets say that they are both squares of different sizes. So, if I would want the center of each of the squares to line up with each other, I would expect that I would first have to do something like create a diagonal construction line in the square in each plane, then somehow align the center of these two construction lines.

Well, I have attempted to do this but failed. What would be the proper procedure be to line up these squares (or whatever shapes they happen to be)?

Thank You

Tom