Mockups and wireframe design will save time and money. Most executives make decisions better with tangible examples. Mockups and wireframes help to educate the buyer on options and helps to provide a process for developers to solidify the end product. This process is essential to avoid confusion, improve communications, and plan work.

Likely, the cheapest and fastest method of modeling a website or application is to simply create a graphic representation of the site or app in a design tool like Adobe's Illustrator or Photoshop, then slice up the graphic parts when it goes into production. However, for more complex flow concepts wireframe tools are useful.

Wireframe tools
• justinmind
• MockFlow
• Pencil Project (open source)
• Mockingbird
• Serena Prototype Composer
• Cacoo
• Denim
• ClickDummy