Your wedding day should be one of the happiest days of your life, making it as stress free as possible however is an entirely different story. Having attended and assisted in many weddings, one thing that rarely ever happens is proper time planning. Since the vast majority of the weddings I photograph are LDS Temple Marriages, I'm going to focus my advice that way.
A Temple Sealing generally takes anywhere from 30-60 minutes start to finish. Usually your Ceremony guests start exiting the temple about 45 minutes to an hour after your sealing began. You, however, will take longer. On average the Bride and Groom come walking triumphantly out of the Temple Doors about 90 minutes after the sealing begins. So, if your sealing was scheduled for 1pm, chances are you'll not be out and ready for your pictures until 2:30. On busy days, the exit could be even later!
At this point, you're on cloud nine and your head isn't totally in the game; now it's time to shift directive power to your photographer. Previous to the wedding, it's a wise idea to get a list of group shots that you want with your family and friends. Once you're out of the Temple, the photographer should have that list ready to go, and they should be ready to direct the groups and get those shots taken care of as quickly as possible. Having that list only expedites the task.
Even the best organized group shots can still take about 30 minutes to complete, so be sure that everyone there can plan accordingly with the tasks that they might have in helping with your luncheon, reception etc. After that, it's down to you, your new spouse, and your photographer. Allocate as much time as possible for those photos; they're generally the ones that you'll be hanging up around your house.
I'd even go so far as to suggest taking these pictures before your wedding day, on a weekday. First, you won't feel a crunch for time, and secondly, weekdays are a lot slower on the Temple Grounds; you won't be waiting for the various must-have shot locations. Something else for your photographer to take into consideration is the lighting, you'll be able to take those pictures with the best possible outdoor lighting. However, don't leave all the preparation to the photographer. Do the best you can to spend a few, romantic hours with your fiance to put your stresses behind you and put your love right on your faces. Even the best poses in the best circumstances are ruined by the wrong emotions that are expressed in your eyes.
After your post-wedding photographs are done you'll run off to your luncheon. I've never found these to be very good photographic opportunities; so it's entirely up to you on whether you'd like your photographer there or not. If I may add though, take into consideration inviting the photographer to join you at the luncheon; remember, they're spending almost as much time invested in your wedding day as you are. Photographers get hungry too.
Finally the time of the Reception arrives. Most wedding parties plan on taking a 2nd set of Family photographs here, when everyone is dressed up. If taking these pictures is something you'd like to do, keep this in mind: No one will be on time. If you tell everyone to arrive one hour prior to the start of the reception, don't count on having everybody there until 30 minutes, and even though don't count on everyone being ready. Tell your family and everyone else you'd like in the pictures to arrive 90 minutes in advance, this gives them a 30 minute late cushion that I promise will be used.
I hope these time tips help you out in your wedding planning; there is a lot to take care of in just one day. It's also not a bad idea to talk to other friends that have been married recently, everyone will have their advice on how to make that day go as smooth as possible.