This may involve fishing it through another wall cavity or out a small hole drilled in the floor.
How to drop wires through wall from attic.
Run the wire or cable to its destination.
Depending on what the wiring is for this may be go through the drywall to the ceiling for instance for new lighting or be farther down on a wall.
Drop the string and catch it in the wall cutout and use that to pull the cable through.
Then pull the cable through the wall plate and out the next wall box opening.
Use a piece of string that you can add a small weight to such as a steel nut or whatever you can find.
If the wall above runs parallel to the attic or basement joist this cable will be attached across the side of a joist.
Roll out the cable through the basement or attic space to the next box location.
If you re working from the attic you can drop a weighted string down wall cavity then attach the wire to the string and pull it through.
Cut the cable leaving plenty of slack and feed the cut end into the wall cavity and out through the wall hole as you did with the first box.
Cut the holes that the wire will pass through to enter and exit the attic.