First, you don't gain much by installing a box without wiring, since wiring is usually the hard part of a future installation. Cutting a hole in the wall later on is very easy, but then how do you get the right wiring run to that point?

The most flexible method would be to run all the projected wiring, cap it off properly in the boxes, and then install a blank plate. However, even then you might not really know now what you need in the future. I assume that some future wiring may be 120 volt, and some may be low voltage (sensors, network lines, controllers, etc.). If you do both low and high voltage, just make sure you separate the 120 volt from low voltage wiring and use separate boxes.

One idea is to pull all the wiring to the areas where you expect to need it, but install the "future" electrical boxes with blank plates and capped wires at receptacle height instead of switch height. This makes them much less visible. If you need to add wiring later it would be easy to run up from receptacle level up to a box mounted higher on the wall.

Bruce

If there is an unfinished attic or basement above or below, you can run a length of conduit behind the finished wall to the location of the possible future device now and fish in the wiring later. A blank-off plate can be placed at the device location now, or you can keep a record, and pictures, of where the hidden conduit is located. I've done this when the HO wasn't sure if they would need CAT6, COAX, or speaker wire.

I was just coming to ask a similar question as we will have the roof off and a few walls open soon but later will we replace the electrical panel. So I want to pull some wiring now and just have it "sit" near the panel ready for connect for some receptacles and lights.

So how exactly does one "cap" the wires in the electrical boxes where the other end won't be live until later? 1) Wire in the ground, 2) put a wire nut + tape on each the hot and neutral and leave it as a future open circuit when we put a breaker on the other side later?

In most cases you just cap off each wire with wire nuts on both ends, and then put a blank plate on the box. If you have a metal box (not plastic) you could connect the ground to the box, but there is really no need if the wiring is disconnected on both ends. On the panel end you need to make sure the wiring is marked (and capped) and left outside of the panel with enough slack for a future connection.

Bruce