The other title of this question could also be: How to improve my creativeness?
During the past years I noticed that a loot of my small applications that I write in my free time to ease my life could also be useful for some of my friends. They asked me to get them a copy. Even if the applications are working as they should I feel a little bit embarrassed because they GUIs are all looking really ugly.
The problem is, I always used standard and default-looking Buttons, TextBoxes etc. Now I thought about how to improve this. And yes I know it is possible to use themes, ImageButtons, ColorBrushes and so on. And now the real problem is:
I can't really see which colors fit together and make a good design. Are there any techniques, books, other resources that help to improve to get a feeling for good designs, color combinations, UI element choose?