I have my first wedding cake due this Saturday. Which I have had to rebake a few sizes. I tried to bake on all of my oven racks & all the cakes I had on the bottom burned on the bottom. If that's the least of my problems I would be ok with that. 
It's always tempting to try to cram your oven full of cakes - after all, it saves time, right? Except they take longer to bake......and then of course rebaking some....... I've made this mistake!
I would next time try a few baking sessions instead of one or two huge ones. In a standard home oven I wouldn't put more than 4 pans in at once, 2 if they're 14 inches or bigger. And it helps a lot to rotate halfway through...CAREFULLY though since the batter will still be liquidy in the middle and might slosh a bit.
You'll be great though! Good luck! 
I did my first wedding cake a few weeks ago...so this might help...
Even though it is obvious what you have to do to decorate a tiered cake, I wrote each thing down because I knew I would be tense and probably tired.
That really helped...I wrote down things like, buy ribbon and foam board, ...decorate cake board, make triple batch of icing, etc...
I know I would have forgotten something and it just reduced the stress for me...I had stuff spread out the week before as there were things I could do early like make flowers, cut out foamcore boards and decorate the cake board...they were things I didn't want to deal with at the last minute...
Keep focused, if you have a problem, just sit down for a few minutes and think things through..
The biggy is, although you may see your own "flaws" as we all do, it is very unlikely that the bride or guests will see any...so don't worry too much and have fun!!!
You will have such a good feeling and gain confidence once it is done!!!
Also, everyone here on CC wants you to succeed and will do what we can to help you through any little thing!!! 
You can do it!!!!
HTH
Jane
Thanks guys for all the kind words & encouragment. Jane what is foam board? I just use regular cake board & wrap them.
Foamboard or foamcore is a type of board that lots of decorators use between layers if it is stacked because it is very strong and lightweight...you can buy it at Michael's and probably any art store..
Just trace out the size (I use the bottom of my cake pan)..cut it a little smaller ...I use an X-acto knife..
The advantage with it is that you can push a sharpened dowel from the top of the cake thru to the very bottom...easily...then the cake won't move at all in transport..each tier will sit on a round/square of foamcore board.
The foam is sort of sandwiched between sort of a waxy type paper that is greaseproof and holds up better than cardboard IMHO.
I learned that here on CC and believe me, you will love it!!!
HTH[/quote]
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