1 - "Get a good night sleep"
I know it may be hard to imagine a bride actually going to bed early before the wedding day but it can be done. One trick, is I have everything ready the day before by asking myself "If the wedding was to happen today would I be ready?" From the bride and groom perspective, all tasks for the wedding should be planned for completion as if the wedding was to be held the day before. Hence, the day before the wedding should be dedicated to rest and relaxation.
2 - "Eat and be merry"
Make sure to eat and hydrate yourself throughout the day. I always have a bottle of water and snacks packed and ready to satisfy my cravings throughout the photo session. Alright, honestly, my beautiful assistant (wifey) usually makes sure that my belly is full and that I'm hydrated. I suggest that the bride/groom assign someone with the important task to provide drinks and snacks to the entire Bridal Party. It doesn't have to be fancy but just enough food/water to avoid the wedding party from becoming famished or de-hydrated. Trust me, you and your bridal party will appreciate it.
3 - "Why prohibit what you can't prevent"
This is actually a quote from Napoleon that I try to follow this philosophy not only during my photo sessions but throughout my life. While I always feel the initial nervousness/excitement before a photo-shoot, during the session I try to stay calm and have a great time. I don't sweat the small things but rely on the careful planning and additional help from my assistant (wifey) to handle unforeseen events. For the bride and groom, I encourage you to have a stress free day as well. Assign not only your wedding activities but the wedding challenges to a trusted wedding coordinator. Advise them to make your life easier by having them make the decisions for things that may go wrong. And for those items that require your input don't stress the things that are out of your control. Rely on your careful planning and people you trust to make your day a special day.
If you are able to put these Zen habits into place you can almost guarantee a great time at the wedding and you will appreciate your day even more after reflecting back on your day through your wedding pictures.