How much fabric do I need for a Tufted Queen size Headboard?

I'm remodeling my bedroom and decided on making my own headboard. I have never done it before,so I'm looking forward on building it. I just need to know how much fabric to buy. Keep in mind that it will be tufted with buttons. I want to make the headboard slightly taller than the normal height of a queen. The width will be the same. Any advise will be helpful.