Specifically, if you live in or have lived in Arizona, California, Kansas, Massachusetts, Michigan, Missouri, Nebraska, Nevada, New Hampshire, Oregon, South Dakota, Tennessee, Vermont, West Virginia, Wisconsin, or D.C. and bought milk (or fresh milk products like half & half, yogurt, cream cheese, and others) in the last 14 years or so, then you can file a claim requesting a payout. Although the settlement doesn't require you to provide proof that you purchased milk, you'll have to declare "under penalty of perjury" that you bought milk or similar products in the eligible states during the eligible time period. The claims are due by January 31st and can be filed via an online form or by mail.
Depending on how many people apply for the cash, you can score anywhere from $45 to $70, although there's a chance the payout could end up being $30 or lower, according to the official website for the settlement. Of course, you should read over all the legal fine print on the settlement website before demanding the cash, but hey, it's free money. Go get it.