I have designed about 30 applications from Commodore 64, Amiga, BBC Arhcimedes, Windows 3.1, n64 through to Vista and Embedded deivces
1. Do you have a vision or not? And who is going to use it.
If you don't then use a committee method to design your UI. Say bye-bye to what you want.
1. If you do have a vision then get your needs/features down on paper
2. Define the platform/platforms you are planning your application to run on. (things like screen aspect, minimum/maximum resolution and input device are very important considerations.
3. Start to mock up designs and position the features you are planning
4. Start to create working mock-ups of key interface elements
5. Start to get feedback on the two or three ideas you have (try getting people to see the idea you like the best - explain why)
6. Do a prototype (even if it ends up as a commercial prototype)
7. Evaluate the issues people have and the way people use it. Create a new version if your prototype is unusable - otherwise let it grow as much as it can.
Our country has plenty of good five-cent cigars, but the trouble is they charge fifteen cents for them.