Well what are you using to wash it? Any particular methods?
There is a thread on here (i think) about how to clean a car, if not, it will be on one of the links in this section, might be detailing world. Not sure.
So yea, make sure your using the right stuff to clean it (the most important is not a sponge)
When its all done, give it a polish.
2 simple steps to making it look nice.
As i said, the guides and the sites will tell you more things you can do, and it is worth doing them - just depends how much time and money you have!
Also, there are products out there to get rid of scratches
So go have a look around and see whats what