How do you create a good world for a RPG Mechanics Verse?

I have wanted to create a RPG Mechanics Verse, but im not sure with the worldbuilding.I'm ok with any system (possibly one similar to Erfworld) but I'm most comfortable with GURPS 4th Edition.How do I do this?

At it's fundamental level a Mechanics verse doesn't make sense. So if you have one don't try to think too hard about the implications. Just enough to find a joke.

Otherwise, start with a few land masses. Guess what the climate should be and rationalize it later, toss in some people and cultures that work with the places their in, steal from IRL cultures whenever you can get away with it, come up with some interesting stories for their history, draw out some political borders, and find the most entertaining people you can imagine and put them in charge.

What are the major themes or your favorite aesthetics? Dn D might have started out more with themes of heroism, whereas the urban fantasy World of Darkness might have been more about angst. Exalted or Weapon of the Gods might be about different levels of greatness. Themes that go along with the plots would be up to the game runner, of course. My World of Darkness team made it a zany comedy that involved lime jello in a gangster's swimming pool and a rubber chicken. But the themes that you personally feel most important to explore can lead to the sort of world that you would like to make.

What government would it have? What technology? How diverse and broad is the scope? Is it based on aesthetics or cultures in a specific region, or a period in history?

I'd recommend starting with your favorite, if you have one. I hope this helps.

Thanks

Stress-test the thing.

Put yourself into the mind of the most devious, tricky, loophole-abusing power-hungry munchkin you can imagine, and do everything you can to ignore the spirit of the rules while sticking to the letter.

Then model the effects of a whole population following in his footsteps, and adjust the society and technology accordingly, because that's just how humans roll.