Best way to chain an electrical outlet?

I have a data home run (telephone, Cat5 and Cable TV) where I need to add an electrical outlet to power a data switch. The HR is right next to my breaker panel and there is an unswitched electral outlet 3 feet directly below the HR. What is the best way to wire the new outlet? Should I daisy it from the outlet, or run the wire first to the HR and then down to the outlet? I'm now sure at this point where the wire to the existing outlet originates.

Best way to chain an electrical outlet?
it is easiest way to run vertically as there is no stud usually on the way.if horisontally from main box you have to cut sheetrock.For the home owner it is more complecated to repair this holles in walls after.
Reply:install it vertically below ; in the same stud bay or you can drill through the side of the electrical box and the stud it's mounted to ; to get into the next stud bay, then go vertically down . remember about the drywall repairs you may create with thinking first
Reply:I am a master electrician with 13 yrs in the trade. The easiest way to add an outlet is to call an electrician. And give him $200 buck so he can do it right