People who have done it will tell you that how an idea is presented impacts its appeal. Below is a checklist of ways to present your idea.:

A presentation.
A feasability report.
A mockup out of cardboard.
A prototype.
A 15-second Elevator Pitch. [What is it? What problem does it solve? Who is it for? Who are you?
Draw it out.
A mind map. [especially of it is a book[
Results from a survey.
A poster.
A 3D Walkthrough.
A simulation.

Of course, I know you know each of the above choice will fit a particular kind of idea. For example, archtects will use 3-D models.
Also read this blogger's report about presenting his idea:

1. Imagining your own examples of how the product would be satisfying, like the mad libs group, results in greater satisfaction.
2. An illustration of the idea makes the implementation of the idea more concrete. It’s more real. There is less interpretation. People judging the idea don’t use their imagination of the product. It’s not their examples of using the product. It is someone else’s idea, implementation, and examples.

Also Read:

Be Remarkable #80: Share your Idea (at least do something about it)