One Simple Rule of Proportion: Two-thirds
It is a simple rule of proportion, merely let your eye divide one-third, two thirds to keep things a bit more interesting.
Take your living room; the furniture should take up two thirds of the area, leaving enough floor space for easy traffic flow. The painting you hang behind the couch, table or above the fireplace should be approximately two-thirds the width. Your coffee table should be two-thirds the width of your couch. The accessory on the coffee table – the flower arrangement – should be two-thirds the height of the vase.
If you’re shooting snapshots or designing artwork,two-thirds will have more appeal. When symmetry becomes the focal point, the balance becomes mundane and will bore you. For example, the first painting of the sailboats has an uneven amount of trees on each side. This creates greater intrigue than the painting with equal amounts of trees between the boats balanced in the middle. Enjoy this simple 2/3 rule!