I love The Boondocks.
Anyway, I think step #1 to showing the world you're not racist would be to make a heartfelt public apology. That seems like the logical first step, and it was one that Thurmond never made.
After that, it really depends on degree. I mean, someone who just used the n-word every once in while and made some derogatory statements about blacks to their friends while in the comfort of their own home, but later realized that they were wrong -- they have less to make up for than somebody whose racist actions helped lead to the death of at least one black man, you know?