如何分享一个iAd广告横幅横跨view的?

I am making a iPhone app, I am currently using iAd's in my view's. I've read something about apple recommending to share the adbanner's through out the view's. How can i do this because I have read the apple documentation and it was not clear enough and i was confused, please help me, if their are any tutorials please tell me or just answer and point me in the right way. Currently I have a ad for every view controller and it runs nice but it comes with a error: Too many active banners (10). Creation of new banners will be throttled. Please help, i am using storyboards and the latest Xcode :) thanksI am making a iPhone app, I am currently using