I love gallery walls when everything is in its perfect place.  I think I must be worse at deciding on the perfect place than most because I never get it right the first time.  However, I have found something that works for me.  At least, it works when the wall has to be painted anyway.  If the wall needs to be painted a new color, and will require two coats of paint, I like to paint on one coat and then play around with the placement of my items making up the gallery wall.  I have never had much luck with marking out the spaces on the wall with painters…