There are many designs for floating bed frames on the net. i kept a few of them in mind and figured it out as i went along. the one dimension i knew was that the frame surrounding the mattress had to be 80"x60" on the inside.. Help with building a platform bed frame hi everyone i just moved and need a new bed. i want something simple, and hopefully with some storage underneath, it will have a foam mattress.. 3. diy hotel style bed frame and headboard make a perfect hotel style bed! learn all the tricks to making the perfect bed frame and headboard that looks just like those luxury beds at the fanciest ( and comfiest!) hotels!.