What is the time of the ceremony if out doors?
the position of the sun will determine the lighting. The evening is the best as it produces a very romantic glow.

If you prepare a time line for everyone, make sure the photographyer gets a copy! Make sure they see it at least a day before the cermony.

What clothing is apprpriate for your wedding. Be sure to give them Suggestions.

What is the wedding theme?
This will help them shoot pictures that fit with your theme.
Example: if it is a cinderalla princess theme, the photographer will want the pictures to look formal, romantic and glowing. If it is a outdoor summer theme, they will want the picture to look fresh, floral and have a rustic feel to them.

How do you feel about your photographer moving during the ceremony?
-to the rear?
-in front of the spectators?
-from the aisles

Do You want "group shots"?
If so, list those in each shot. IE Bride Groom Mom Dad, Bride Groom Mom Dad Sister Brother and Uncle Jimmy, Bride Groom Best Man Maid of Honor etc.

is there a garter belt/toss as well?

Make sure your photographer is well aware of any special happenings during the ceremony and reception.
Do you have other sentimental portions of the day---like an old locket, a ribbon in your hair from mom's bouquet, grandma's pasture boots, etc?

Will you have printed programs for the ceremony?
Some great atomospheric shots can be captured using sentimental keepsakes such as programs, handmade signs, the brides gown hanging by a window.

What are you planning for your cake?

Would you like Special friends to be photographed when they are around you?

What should you and the photographer do about relatives that may request shots of "all the cousins", "all the relatives from back East" or "with the grandmas"....etc.
you may need to fend off well meaning relatives and friends to get all that you want from the time you have with the photographer.

Any special venues for photos on your ceremony site that you would like with your bride/groom?
some by the barn, the fence post, the back door of the house, the Church porch railing...etc.

Is the Groom allowed to see the bride before the ceremony?
This will determine the pictures and time allowed before the ceremony, and could pose for some great "first laid eyes on my Bride" shots.