While watching Will Harris’ Rockstar Hour today, I recalled how many people I’ve come across that did not know how walls worked in Revit.¬† While the TotD is not designed to be a full blown lesson, I have prepared a couple tips for placing walls.
1) Making a box of walls in a clockwise motion will result in the exterior layer of the wall being on the OUTSIDE of the box.  Making a box of walls in a counter-clockwise motion will result in the exterior layer of the wall being on the INSIDE of the box.  Use this knowledge to make sure you are placing a wall with the exterior layer in the correct orientation to avoid problems later in your project.  This is demonstrated in the video below.
2) The double control arrows ALWAYS appear on the exterior of the wall you have constructed as demonstrated here:
As always, I hope this helps and I hope you join me for the next TotD!
-Carl