How to Build a Wall True to the Space

Marti and I often decide to add new features as we build. In the last remodel video, Marti asked about shelving for her side of the bed, and we added framing to the inside of the wall to support their installation. Now we want to add a wall to make it easier to hang shelves on my side of the bed. This wall will be a little more complicated because the space is we are building in is not level, plumb, or square. This wall will need to fit a similar space in a similar way but for it to be "true" (apparently in line with the other construction elements) we have to make some adjustments. Oh, and the main electrical conductor for the room will also pass through this new wall.