Testing Usability User the application yourself - as soon as possible. You'll find usability problems this way (e.g. too complicated wizards, commonly used options not found in the toolbar, etc.) Let some "typical user" use the application, and watch them as they do so. You'll notice how they use your application and see how intuitive and comfortable it is for them. Place some logging mechanism in the application, so you'll be able to see which options users use and which not, and in what order. Looking at these logs you'll see which options to develop more for next version, which may be removed from the toolbar due to lack of usage, and which options are often used together, and could be turned into 1 meta-option, or a wizard.