The universe is a place of balance. For every goody-two-shoes-puppy-saving-hero out there, the universe needs a paragon of evil. Being an evil villain is a rewarding way to make a real difference in the world and crush it mercilessly under foot in the process. Unfortunately, there are very few evil villain training programs, and they are notoriously hard to get in. Luckily, there are real opportunities for self starters in the booming industry of evil villain operations.
Establish an awesome secret hideout. It's all about location, location, location when it comes to secret hideouts. Skull shaped uncharted are an absolute classic, but they are never on the market long! Of course, there is a great deal going for an under-volcano base when looking at heating and energy costs, and it is hard to beat the view from an awesome orbiting space station or secret moon base.
Recruit an army. When the good guys come, there needs to be as much fodder around to take the brunt of the avenging fists of justice. Plus, a well trained evil army not only makes a great personal staff but also an impressive posse. Be sure to follow all worker health and safety regulations; dealing with superheroes and secret agents is easy compared to getting a visit from OSHA.
Hire at least one top shelf sadistic sidekick (of course, the more the merrier). This is even more important than a huge secret hideout or vast army of henchmen. One really crazy iron-fisted lackey to destroy enemies in some type of signature manner really goes a long way to establishing some serious street credibility, so go all out. A tip: super-hot ninja girls with repressed gender role issues are the next big thing in villainy!
Outline a sadistic plan for global domination. Something with laser satellites or nuclear blackmail... the details aren't terribly important early on as long as it is clearly established that the world will either be crushed into submission or completely destroyed to clear the way for an entirely new order (guess who gets to lead that!).
Create an intense, lethal rivalry with a major agent of good. Too many wannabe villains are out there claiming to be evil, but no one really cares enough to even try to stop them, and soon they are back to being the night manager at Kwiky-Gas. A villain is only as good as the hero they are up against. Anyone can fool the police but not really be an evil villain (for example: is OJ a real villain or just a guy that beat the cops?). A big league villain needs an A-list adversary. Select the agent of good that is most appealing and viciously blow up their wedding or something to attract their attention.
Have fun with it! This is much more important that it seems. Evil is about doing what one wants when one wants, not fretting about schedules and requisitions and jail time. If a villain is not really enjoying what they are doing, the press will chew them up and spit them out in no time!