With a mock building tool can greatly reduce the planning time and get a clear picture of what information will be needed on each page.



Here are a few of them:


Pencil - free and opensource tool for making diagrams and GUI prototyping http://pencil.evolus.vn/en-US/Home.aspx


Mockup Builder - http://mockupbuilder.com/


Cacoo - http://cacoo.com/


MockFlow - http://www.mockflow.com/


LucidChart - http://www.lucidchart.com/


HotGloo - http://www.hotgloo.com/