1. Make the ringleader of your baddies a foreigner. Undeniably, this means they will have a noticeable accent that forebodes their dubious intentions long before they're revealed. Extra points for a Russian accent, involvement with the Russian mafia or dealers in the blood diamond trade. Golden star for two or more!
2. Your character must be the scum of the earth, with no redeemable qualities whatsoever. If they oppose the main hero, they must be scum, because heroes and heroines can't have flaws and are always correct in their endeavors. Some helpful, unforgivable archetypes include: child pornographers, rapists, serial murderers, and abusers of large quantities of drugs. Bonus points if he snorts the drugs off of or with a stripper...and then kills her.
3. Your antagonists will usually be male and older, but whether male or female, they will be unattractive in both personality and appearance. If you choose to subvert this trope, you have two options: make the character a charming psychopath or a cunning thief. Both of these types will eventually get away and the audience will cheer for them because they're "not as bad" as other baddies featured in the same story (see #2).
4. All bad guys must have some form of facial hair.
5. All bad guys have unlimited amounts of disposable cash and henchman. Because of this, they are not afraid to kill employees to make a point.
6. Bad guys really know how to rock a three-piece suit.
7. Bad guys are often cryptic and deceptive and have an elaborate cover up scheme even when it would be easier to be upfront about their badness. Why? Because "Screw you, I'm awesome, that's why."
8. Exploitation and/or infiltration of local and national government is a must. Law enforcement officials can't touch them, and politicians are all scrambling to get into the Baddy's favor.
9. A goal of anything less than world domination is for amateurs.
10. Bad guys have no qualms with killing their own employees execution style, but when it comes to the protagonists? Heroes and heroines will be tied up and left locked in a room, only to escape and prevail over the baddies each and every time.