First of all, you need to consider clothing. Normal or dark-colored clothing is the best. Darker clothing will ensure that the ring shows up nicely in the photographs. Also, it makes for better contrast if you’re considering an outdoor photography. But, the couples should not wear the same colors.

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The simplest, classic pose is to have the bride leaning against the groom’s chest. She should be on the right so that the ring on the left finger is to the front. You can also have the groom seated and the bride standing behind him with her hands over his shoulders. Again, with this classic photograph, you will display the ring very nicely.
But, if you want more natural poses, you should try to get candid shots. This often can be done by letting the couple believe that you are changing film or your battery. Have a shutter release that you can keep in your hand. Watch the couple out of the corner of your eye. Many couples will take this “relaxing time” to talk or laugh together. These types of shots make for realistic poses and very memorable photographs.
Another way of creating unique, candid shots is to bring in a prop that represents something that from their relationship, i.e. their first present given. You can also take them to places that are memorable to the couple. For example, it would be memorable for them to take pictures where they had their first date or where they met.