When you build your application, don’t ignore the icons and graphics. You may need some specialized graphics or icons for your application but in a lot of cases you just need some simple graphics for a button or similar. You may be tempted to just use the same icon throughout the app with the idea to come back later and add some graphics all at ones. I’ve found it’s better just to take a two-three minute detour to go ahead and find an applicable graphic add it to the app, see how it looks/feels as you use the app and add additional features and potentially replace it if necessary.
One place I’ve found a great source of professional icons is from Syncfusion Metro Studio, what I like about their icons is that they have an app where you can search on icons by category and name. When you find one you like you can customize the color, size and border. They also go really well with a metro application.