In hot weather have one of the drivers carry cool refreshments and "nibbles" for the bridal party
If you have young children in your bridal party, the long day and heightened emotions can cause the little ones to play up. If this happens, let it be - but have someone delegated to handle the small people. After all, this is your day.
Have Fun! Even if you normally hate having your photo taken, get into the spirit of the day, let go, have fun and pose. Have a practice in the mirror, it makes a huge difference.
After 30 yrs photographing weddings, my best advice is to RELAX. Don't stress, once the big day has arrived there is nothing more that you can do except enjoy your day!