I have no doubt that you want to get the best photos in your life. Try to remember a few simple rules and you most probably shall have them:
Make a list of setups for family and group portraits. Always invite photographer to your rehearsal. Appoint someone (Best Man is the best!) to assist photographer to organise your guests. Try not to look down or wink, instead keep your eyes open even wider than usual and smile with open mouth. Choose sunny (not shady) spots for shots outside. Although you shall be nervous and excited, try to move slowly and do everything with importance. Look at the photographer, not guests, and when you look at each other - don't close the view of your faces! Use steps and stairs for group portraits. Ask me for more tips!