help with wetsanding

Thanks to Grant for explaining what type of supplies to use when wetsanding and the pics of the process, but could somebody explain the steps that go into wetsanding in a little more detail? Do you spray water on the boat and start sanding? or is there a certain type of "wet" sandpaper that I need? I start to get sick when I think of actually putting sandpaper to my boat's gelcoat. But I have some serious scratches that need to be fixed. Thanks for any help.