While it's important to choose an affordable wedding photographer, there are things you can do that will make your photographer's life on your wedding day much easier.
However long you think it's going to take to get ready, add an hour to that total. Trust me.
Know what group and bridal shots you want beforehand. You can always add more, but be sure you know which ones you must have and get that list to the photographer or fixer (see below).
If you want or don't want dressing room photos, make that known ahead of time so there's no surprises at the wrong moment.
If possible, designate one of your guests ahead of time to be the "fixer". This person can help round up people for the group photos and keep them from wandering off in between photos. This can save a lot of time. I've found that aunts and mothers-in-law can work well for this because they know lots of people and generally aren't shy.
Watch out for churches or venues that have strong light behind the altar. A photographer can compensate for this, but it rarely looks as good as a shot that doesn't have it.
Ask that the altar area be as well-lit as possible. The guests' seating doesn't require as much light, but the more light on you, the better the photos will be.
Give your photographer an itinerary of events at the wedding and reception. That way, they'll always be in the right place at the right time.
When setting up locations like where the cake goes and where you will dance, think of your photographer for a moment: Are there streamers on the cake table that might block the camera's view? Are the buffet tables going to be in the background of dance photos?
Cake cutting: Take your time and listen for directions from your photographer. If you intend to smash your partner in the face with cake, let the photographer know early so they can be ready for it.
At any point where you want a particular photo, one you didn't think about earlier, just ask. Any photographer worth his fee will be happy to shoot any shot you want, so long as it won't get them injured, killed or arrested. Remember, in the end, all the people you're paying work for you.
Relax! At the end of the day, no matter what happens, so long as you are married, it's a success.