How to add second receptacle to the same line?


I know it sounds rudimentary, but I'd like to make sure I'm doing it right.
I have two dedicated power lines with one duplex receptacle on each, that I want to add another two duplex receptacles to.
I have an idea, but not sure it's the right one. I don't really want to call an electrician for that. I installed receptacles before, so that shouldn't be a problem.
thanks in advance
maril555
It's easier to just add power strips with the surge protection, but...if you insist, google it and probaly use wiremold rather than cutting holes and reinforcing the boxes. Power strips your best option tho.
Wanted to add to my previous post. That dedicated line is no longer going to be dedicated, it'll be a branch circuit once you add recepts to it.
Mental? ok, but you make sense. (sometimes sadly lacking in these forums (fora?)
Mental,
Maybe in a strict technical terms it's not dedicated, but it is dedicated as far, as nothing else is on the same line