I would find it very difficult to actually be "evil"... I'd want to shove in all manner of legal changes and restructuring in the name of libertarianism.
Ok, ok... if I wanted to be "evil" overlord I suppose I'd light off a "benevolent" cult of personality, foster a massive military buildup, and slowly begin taking over the world, starting with Africa. Lots of space in Africa. Lots of resources too, lots of room for factories, secret bases... and equatorial land for space access. And I'm not talking genocidal efforts here either, somebody's got to run the place... lots of engineering schools, buying people off, and unfortunately quashing of dissidence. Cooperate and life is very, very good. Otherwise you're in hell.
And, of course, there'll be a complete and utter communication shutdown for the entire continent.
Timelines will be over one generation... best way to have an army of total sycophantism is to start training from birth. Lots and lots and lots of fission plants using nigerian uranium will get built to run the desalinization plants on the west and east coasts that'll pump water far inland and start reclaiming the desert regions. That'll also have a handy side effect of allowing for uranium enrichment for... ah, let's say "higher energy' projects.
When the time comes to "spread", it'll be initially by controlling the straits of Gibraltar, the Suez canal, the Red Sea, and the passage around the horn by naval and aerial means. If that's not enough then we'll destroy the oil pipelines around the black and caspian seas and force oil distribution by ship, which of course, we control. Oil supplies will be nearly pointless for us because by then we'll be running greatly on nuclear fission and geothermal energies tapped from under the Rift. But, everyone else wants it, so into the middle east we go, and we'll make sure that the locals understand that this is a dhimmitude in reverse... and undergo the same kind of societal turnover as in the beginning. We're on to the third generation by then, and I'm probably dying or dead so the whole thing will likely fall apart as most cults of personality go.... or it'll get worse; there'll be a Stalin to my Lenin. By then we should be able to pave the world over in glass several times over and have a 3:1 naval and air superiority with nuclear powered vessels in size down to destroyers and littoral ships, and hopefully extremely large nuclear air platforms, so anyone who wants a piece needs to deal.
Oh, did I mention the trans-equatorial nuclear railways? A nice 7-8 rail remote fission-electric powered, 200mph rail transport system around the globe? Of course it'll be transatlantic at first, and then spread east from the state of Somalia, with spurs heading north from the power plants... it's vulnerable militarily but it'll be one hell of a way to "unite the world" and extend a social hand while I hold the other with it's dagger behind my cloak of diplomacy. Spys and saboteurs, folks, probably one in every shipment. In *my* land in the mantime everyone's radio-coded with their DNA signature and we'll have developed near-instant sequencers in short order to ensure that those who say they are, are... and anyone not is executed on the spot.
And when global domination is complete, time to snag the moon.
You *did* say evil, right?