Both of the manufacturer links below provide an opportunity for you to visualize what your home will look like with different color combinations.
You can choose a home style that is similar to your home. From there you can choose different roofing/siding colors and styles.
If you want something more specific to your home, you can upload your own photo for customization.
If you are perfectionists, both sites can do the work for you for a nominal fee. Please see each specific site for details.