Wash, rinse, Wax & Repeat...
I have a Black Expy, and have owned many black vehicles... big thing is just to keep it clean, and keep a good wax on it. Stay away from car washes, and do it by hand with VERY soft cloths. Black will show everything, even the most minor scratch. I have 3 kids, and when the truck is a little dirty, the hands rub against the truck if you don't have a good wax coating on, those little fingers just scratched the paint. I also have my black vehicles buffed & detailed every 2 years.
I'm no pro... but that's my 2 cents.