What will I sleep on? or do I have to build it?

I decided to start all over with this post as I realize I wasn't being to realistic about putting a futon in the van. So now the wise and all powerful Tippy LOL has decided to build a bed. Yep me ...who can't build anything. How do I do that you say? By having our wonderful hardware store cut everything for me and to Have instructions in front of me. I need to know where A is to be screwed with B or I get confused very easy.
http://www.instructables.com/id/Cheap-easy-low-waste-platform-bed/
This site is wonderful I get so may ideas to build something. With this I can build it shorter for the van. I'm going to build it wider than a twin but not a full. Have the legs higher so I store more stuff in there .....neatly.