The first thing you wanna do is save up some money for your Michael Jackson costume.
After you have some money you will need to go to your local thrift store or mall and buy a blue lacy T-shirt, Skin tight gold shiny pants,white tie, pinstripe dress jacket, and a hat with a colored trim matching your shirt, if you can. Also don't forget to get one white glove it adds a lot to Michael Jacksons features and hopefully you get it half off.
Once you have all of the right clothing you will want to get a wig from a costume store or you can just use your own hair and style your hair with curly straight locks for a better Michael Jackson feature. Looking for a picture on Google would be the best thing to do for a perfect Michael Jackson hair do.