Okay, so you want to make a great-looking character?
First, pick a color scheme. Look up some color scheme generators. Next, choose your markings carefully. Does it clash? Is it too soft-looking?
You may want to use different fur textures for your character; the colors may blend better if that's your thing.
But, this is my opinion. A lot can go into a character if you want it looking perfect. I personally like characters with varying shades of brown-beige.
However, as XenonUnicorn said before, it's not really appearance at all. It's more about how your character IS, than what they look like.