Hey Andrew,

Congrats on the wedding work. Depending on the time of day will affect where you shoot and when. Certainly, for mid-day photography, you are going to want to find some nice shade areas...ideally without patches. Try photographing with both flash on and flash off for formals. I agree with Tony - meter off of the face.

If you have a second person, you may want to consider the following things:

(1) Have a reflector to brighten up shady areas.
(2) Use a video light on the couple when you are doing close candid work with them. It creates a nice warm light that is better than flash (which I generally try to avoid).

If you wind up having to photograph in direct sun, you will need to use flash. Meter off of the face and kick the flash up +1. This will help eliminate the shadows that occur on the couples eye's that occurs when photographing in direct high sun. You may have issues with the dress blowing out...so be careful.

Last - try these things out on a dummy (i.e. friend, child, etc) before doing it on the wedding day. Practice is everything.

I hope this helps
James