Peter Anspach has compiled a list of 100 ways to be a successful evil overlord. He probably could have cut it to 50, but nonetheless the list is worth a read. This is "Sun Tzu meets bad action movies":

15. I will never employ any device with a digital count-down. If I find that such a device is absolutely unavoidable. I will set it to activate when the counter reaches 117 and the hero is just putting his plan into operation.

20. Despite its proven stress-relieving effect, I will not indulge in maniacal laughter. When so occupied, it's too easy to miss unexpected developments that a more attentive individual could adjust to accordingly.

29. I will dress in bright and cheery colors, and so throw my enemies into confusion.

58. If it becomes necessary to escape, I will never stop to pose dramatically and toss off a one-liner.

92. If I ever talk to the hero on the phone, I will not taunt him. Instead, I will say that his dogged perseverance has given me new insight on the futility of my evil ways and that if he leaves me alone for a few months of quiet contemplation I will likely return to the path of righteousness. (Heroes are incredibly gullible in this regard.)