I'd be more than happy to help (for free).
To make a map, as said above, you need an idea, i mostly watch something or plan something out to get an idea.
You then need to develop that idea, work on it and get rd of any not so good parts of the map.
When you come to update your map, only add new features if you think all you're previous updates have all the bug fixes.
As for the fame part, you would need a team of professional mappers with professional skills and standards, then your team would be able to do anything you need to happen in the map to create brilliant gameplay, excellent style, and good fun

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I mostly make maps for fun and for people's fun (i hardly made any), but if your team and game is good enough, your game could be better than DotA, or if you're really good, AWA

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Best wishes, good luck

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~Jindo