You could try mocking out your idea using something like http://www.balsamiq.com/ http://www.balsamiq.com/ or http://www.axure.com/ http://www.axure.com/ (I'm n

You could try mocking out your idea using something like http://www.balsamiq.com/ http://www.balsamiq.com/ or http://www.axure.com/ http://www.axure.com/ (I'm not trying to push any specific mocking software). This allows you to describe how you want the system to behave without getting into the nitty gritty on how to make it look good: that is why these mocking systems look as pencil like as possible. Iterate with a designer a few times with these mockups. I would also recommend showing the mockups to your stakeholders and/or customers and ask them what they think. Do they like the flow, etc. Another advantage using mockups is that once you have your mockups finalized, you can start implementing the behavior of each mockup while the designer designs. For this phase, I would recommend using Feature/Behavior Driven Development to drive the development of your code based on the mockups. Use Test Driven Development to fill out the units of your program. Just a suggestion and I hope this helps.