I swear by Edna De La Cruz. She has many videos on youtube. Many of them are on the basic of cake decorating: mixing butter cream, icing a cake, leveling a cake, stacking… You have enough time, that you could learn what ever it is you need to do.
Edna De La Cruz’ youtube Channel: http://www.youtube.com/watch?v=dIXHFqpJK84
My advice would be to research videos to learn the techniques you need and to practice, practice, practice!
You will need to learn how to stack correctly, if you are going to stack a wedding cake that will feed 140 people!
The other advice I would give is to keep your design simple.
If there mistakes in buttercream, you can simply rub them out with a viva paper towel (Viva Paper Towel Method) or you can always stick a flower where there is too bad of a flaw.
I admire your courage. Good Luck to you!
Psalm 127:1 Unless the LORD builds the house, the builders labor in vain.
