Make your ad your self. Stick to the script!
As the ad world gets more & more free form(ulaic) it's becoming easier and easier to sound just like the big boys. I've even heard talk of an advertising machine to replace us all. It still has a few bugs, namely the catalytic flux conception device constantly hiccups rehashed versions of Old Spice commercials.
But all that can now be avoided and all you need is a pen and a product. Give it a try and see if you don't do the ad voodoo that the big agencies do so well. Note: if you put your feet on your desk while filling this out, you will have the appearance of really understanding advertising.
Here's one example for the Mad Ave from MCC