What's the most realistic way to overcome racism?

Educate people about other races, and give them a chance to mix with other races also. Whether it is in a community or at work, just get people to work together (perhaps to solve problems or volunteer etc) and have contact with each other informally. Telling people that racism is wrong is simply stating the obvious. Giving them a chance to know other races would be beneficial as racism usually arises from ignorance and bad experiences. People are not born racists, the environment and people around them influence them a lot, so changing this should help