There really is no easy way. Hopefully, both upstairs and downstairs walls line up. That's first. I usually run mine down close to a corner if I can so that when I get down the upstairs and work my way down I will pull back the carpet. Do not try this if you aren't confident in putting it back right. It's not too difficult. Then I will drill 2 holes with my 1" paddle bit. One for my mini mag lite, One to look thru. This helps you to see your flexbit on the header of the downstairs wall. So you don't have to stress over hitting romex or shooting out the ceiling or wall. If the walls don't line up but are less than 2 feet apart, then you want to try to run where there is a closet. Use the same principle, pull back the carpet, drill your holes, find your header, then fiche from attic to top floor, then fiche sideways to your header to downstairs. I only do these techniques when the customer is desperate to get that outlet in and of course they pay me for my time.
CableSmack
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