Politics
It is a sad fact that politics take such a predominant place in our society. If it were not for politics, we would probably all be living in peace with our neighbors, and have everything that we could ever want. On the flip side, if we were all living in peace, there would be no need for someone to be an Evil Overlord.
As a prospective Evil Overlord, you need to learn politics, and how to manipulate them. There is a lot of power available to the right person, you just need to muscle your way into the right position. Make connections, get to know people from all walks of life. If you have a bridge, be careful not to burn it. Once you have a network of people established, you can wield your little army with precision to accomplish all sorts of tasks pertinent to your take over plans. You can also use this army to manipulate local governments, rules, and regulations, to make your bid for world domination that much easier. Just be very careful to never contradict yourself, or to make a fool of yourself. Unlike Al Gore who is consistently in the news for all the wrong reasons.