Very first giveaway...any advice?

SO, I decided to have my very first giveaway.  I am scared and very anxious I am really nervous that something will go wrong. I am seeking vendors  and will use the rafflecopter widget. Is this going to go smoothly (boy, I hope so). So.....I am looking for any and all advice that may help me make this a huge giveaway and a successful one as well.

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