We all have great ideas. But often they remain in the form of thoughts in the mind. Or maybe you do tell a few people, but even then it’s just words in the air.

One of the important things designers do differently is that they give form to their ideas, almost as soon as they think of them. That form need not be a thing of beauty. It can be as rudimentary as a freehand sketch on a napkin, or as crude as a prototype made from foam rubber. Just the fact that there is a form at all is what matters. When a designer gives shape to an idea—even if the shape is rough and only temporary—it begins to transform the idea into something that is real and tangible and hard to ignore.

“A designer has one foot in imagination and one in craft,” notes Brian Collins (above, left), a renowned designer who heads up a New York firm that bears his name. By being able to envision “what might be” and also having the capacity to draw or build representations of that vision, Collins says, “the designer can put a version of the future in your hands and ask, ‘Is this what we all want?’”

When I was assembling definitions of the word “design” for Glimmer, I thought that Collins’ definition—“Design is hope made visible”—was one of the best I heard. By showing us new possibilities and new visions of the future, design can help rally the support needed to turn those ideas into realities. By making hope visible, designers and innovators can generate momentum for all kinds of initiatives—from the development of new devices or services to the launch of social movements. Collins himself is doing this on behalf of Al Gore’s Alliance for Climate Protection, for whom he has helped design the award-winning “We” logo.

While Collins is using a designed logo to rally people around a mission, the same thing can be done with a simple napkin sketch. Sketching is “the archetypal activity of designers, and has been for centuries,” notes the veteran designer Bill Buxton, who has studied and written on the significance of the humble pencil drawing—not only as a tool for designers, but as a critical element of innovation. To those who think of drawing as mere doodling, this may be surprising. But sketching can lead to invention because it allows for fast and freeform exploration of multiple ideas. A sketch is easy to make (even if you’re not a trained designer or artist: stick figures are generally sufficient), easy to understand, and easy to change. Thus the practice of sketching lends itself to collaboration and experimentation.

You can also go beyond a flat sketch to build simple three-dimensional models—designers often put these together like makeshift toys, using whatever scraps are available. Tim Brown, head of the design firm IDEO, believes in “building to think.” He adds, “Through the act of making things, we find that we learn about ideas.” In fact, design researchers are now discovering that the very act of tinkering with materials and objects can be an important part of the learning and discovery process. The design term “thinkering” refer to the ways in which people tend to learn and develop new ideas as they play around with whatever it is they’re working on.

Whether you represent your ideas through sketches or something pasted together with Elmer’s glue (or perhaps something cut-and-pasted together digitally, using the great DIY design software now available), the point is to get your ideas into a form that enables you to share them with others and get feedback. “You have to scratch an idea out into the world any way you can,” says designer Bruce Mau. And once you do that, he adds, you have taken the first step in turning that idea into a reality.