ac cable connection

whit your past expérience and you opinion, at wich place your best ac cable must be place(if you have several model) in your system?

ex: behind the wall and power dist, behind the amp and the power dist...i know that the answer depend of many thing but i just want opinion.
I would think best would be to start with Dedicated Lines ...2 or 3 for Analog and one for Digital..Then go from there and work your way forward......