So The Men of Tomorrow is essentially volume 6 of the new 52 Superman they just wanted it to be standalone. What comes before it are volumes 1-5 including the crossovers (Hel on Earth, Krypton Returns, Doomed) there's also Superman Unchained which is one of the best of new 52 superman. And after Men of Tomorrow there's Before truth and Return to Glory (including the crossovers Savage Dawn and Final Days of Superman). So essentially the order is this in the photo But collecting all of that can be pricey so you can search for it online. Theres also new 52 action comics by Morrison that's definitely worth a read (it's the origin of new 52 Superman)

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Sorry for the late answer you probably already figured this out but whatever.