This could get long but I really feel for you and want to give you as much advice as possible - I'm not a pro yet but I've had some experience...
I've also been in the same position as you - not quite sure I can do a big event like a wedding, but in my case, I really wanted to try it - because they knew ahead of time it wouldn't be the same as a pro shoot, and they weren't paying me - so they were "getting what they paid for".
I had my D70 which I'd had for awhile but bought an SB600 before and made the mistake of not familiarizing myself with it ahead of time, so I defaulted to the settings after shooting shots too bright and too dark, and after that it was a lot better.
I did, however, learn from that wedding to the next one - the first went fine and I shot TONS of photos (another very good tip - get another 2 GB card if you can and keep going) and they ended up with over 350 good finals that they printed and re-printed...I worked so hard I thought I deserved something for it but learned from that too - a contract or fee up-front (if you want to charge one) is much easier when dealing with friends, family, whatever.
For the second wedding, I had a sample contract (just do a search, there's tons on the web) to use for our agreement, and a sample list of photographs they can check off. KEEP THAT LIST when you go to the wedding - ask someone to assist you even just to wrangle people up and keep track of time, and the photos you still need to shoot.
Get that list organized so you don't have to shuffle people back and forth. Do all the guys first, all one family, whatever - so the wedding party can leave if they want to. If they are comfortable and don't see you sweat, they are much easier to work with. A nervous photographer will make them cranky - it WILL happen!
Time will go very fast and you can't spend a lot screwing around with equipment or looking for people, so whenever there is a lull, shoot - shoot - and shoot some more. People LOVE the children in casual situations, and kids love to mug for the camera - some parents don't get their kids in those clothes often and will love candid shots. I prefer more close-up pictures if it's one or two people, but get all different distances so they can choose what THEY like. Check out what other photogs do or get some wedding photography books for different picture setups, but get an idea of what the bride and groom want ahead of time and make sure you cater to that too.
What I've noticed in all the churches I've been in is I get a very yellow glow - I don't usually set up big lights since my churches have been very small and I can't get much in there but myself, but if you can get a big light in there to help cut down on the low lighting conditions, do it.
Set up your equipment before your scheduled time so you can move freely for the "before" shots - brides love those, too. I have done my weddings from when they get ready to almost the end of the dance - which makes for a long day. Bring water for yourself in case you work the whole day and don't get a chance to sit or even eat - if you don't have an assistant to watch out for you, you could get exhausted fast!
Organize your equipment so pack up is simple - either get some big totes or pro cases to put everything back safe and sound. You're usually in a rush after the actual ceremony to get to the next place and if someone helps you that doesn't know what they're doing, you could have some ruined equipment or lose something.
I have not had much time to do the standard portraits in front of backgrounds, for loss of time, but if that's a "must" for your bride and groom, set that up in a separate room where kids won't be running and you have plenty of space. Outdoors, if you CAN, are favorites too - colors are better and if you scope out the location, you can find some really nice backgrounds for your standard shots.
I could go on and on - and I have - but those are things I've noticed as I've done these events. They're lots of fun and with the right group, you can enjoy yourself even if you're working. If you want to correspond more about this, let me know! I don't mind sharing! Good luck!
I've also been in the same position as you - not quite sure I can do a big event like a wedding, but in my case, I really wanted to try it - because they knew ahead of time it wouldn't be the same as a pro shoot, and they weren't paying me - so they were "getting what they paid for".
I had my D70 which I'd had for awhile but bought an SB600 before and made the mistake of not familiarizing myself with it ahead of time, so I defaulted to the settings after shooting shots too bright and too dark, and after that it was a lot better.
I did, however, learn from that wedding to the next one - the first went fine and I shot TONS of photos (another very good tip - get another 2 GB card if you can and keep going) and they ended up with over 350 good finals that they printed and re-printed...I worked so hard I thought I deserved something for it but learned from that too - a contract or fee up-front (if you want to charge one) is much easier when dealing with friends, family, whatever.
For the second wedding, I had a sample contract (just do a search, there's tons on the web) to use for our agreement, and a sample list of photographs they can check off. KEEP THAT LIST when you go to the wedding - ask someone to assist you even just to wrangle people up and keep track of time, and the photos you still need to shoot.
Get that list organized so you don't have to shuffle people back and forth. Do all the guys first, all one family, whatever - so the wedding party can leave if they want to. If they are comfortable and don't see you sweat, they are much easier to work with. A nervous photographer will make them cranky - it WILL happen!
Time will go very fast and you can't spend a lot screwing around with equipment or looking for people, so whenever there is a lull, shoot - shoot - and shoot some more. People LOVE the children in casual situations, and kids love to mug for the camera - some parents don't get their kids in those clothes often and will love candid shots. I prefer more close-up pictures if it's one or two people, but get all different distances so they can choose what THEY like. Check out what other photogs do or get some wedding photography books for different picture setups, but get an idea of what the bride and groom want ahead of time and make sure you cater to that too.
What I've noticed in all the churches I've been in is I get a very yellow glow - I don't usually set up big lights since my churches have been very small and I can't get much in there but myself, but if you can get a big light in there to help cut down on the low lighting conditions, do it.
Set up your equipment before your scheduled time so you can move freely for the "before" shots - brides love those, too. I have done my weddings from when they get ready to almost the end of the dance - which makes for a long day. Bring water for yourself in case you work the whole day and don't get a chance to sit or even eat - if you don't have an assistant to watch out for you, you could get exhausted fast!
Organize your equipment so pack up is simple - either get some big totes or pro cases to put everything back safe and sound. You're usually in a rush after the actual ceremony to get to the next place and if someone helps you that doesn't know what they're doing, you could have some ruined equipment or lose something.
I have not had much time to do the standard portraits in front of backgrounds, for loss of time, but if that's a "must" for your bride and groom, set that up in a separate room where kids won't be running and you have plenty of space. Outdoors, if you CAN, are favorites too - colors are better and if you scope out the location, you can find some really nice backgrounds for your standard shots.
I could go on and on - and I have - but those are things I've noticed as I've done these events. They're lots of fun and with the right group, you can enjoy yourself even if you're working. If you want to correspond more about this, let me know! I don't mind sharing! Good luck!