Hello im sure you hear this all the time, but I have an idea and im dying to put it on paper but I cant seem to think up any structure to use when writing the idea... I dont even know where to start... does someone know of anything that can help me?

search game design document template on google.com

then edit it to fit your idea, if there is something on there your not sure of the ask in these forums

http://www.sloperama.com/advice/specs.htm

www.jbourrie.com

I have the design docs for Rumble Box and Thelema posted up there... it might give you some ideas.

The best way is to start writing. Put it down in a way you'd understand it. My way is to put down the concepts I may forget later.