You can start with an inspiring quote that says we are all equal as for your introduction eg Harper Lee's quote in his To Kill A Mockingbird. 
note: be sure to have proper citations to avoid plagiarism. 
then discuss your ideas and insights or reflections or personal experiences (if ever) regarding racism. perhaps anything you can say about racism and people being misjudged, like how they might feel and like what if you were the one being misjudged, what would you feel. it might also help, in fact there's a viral video about racism in mexico in which kids there think that the white baby doll is the good and pretty one while the black baby doll is the bad and ugly one when actually those two dolls were just the same; the black baby doll was just painted black/dark brown. 

then end it with a bang like stating things we can do to avoid racism and to have equality.
note: for more impact, you can also state the difference of equality and justice. and have your stand in which is better for the black people. something like that. and it's an essay so feel free.