Wedding rings are a symbol of eternity with no beginning or end. They represent the continual bond of when two people fall in love. The circle of the rings are also symbolize the sun, earth and universe and represent holiness, perfection and peace. The reason the wedding ring is worn on the fourth finger is it was believed that it is the closest to the vein that runs to the wearers heart - also known as "the vein of love."
As a wedding photographer, I always view the wedding rings as art and place them in or around the bride's bouquet, wedding invitation and sometimes with the bride's shoes or jewelry. I usually photograph these shots as the bride finishes getting dressed and before the ceremony. I want them to look like sculpture or a painting.
I prefer not to shoot the rings on the hands as the fingers can be distracting. I use a special macro lens and selective focus to highlight the design of the rings.