But if you're privy to 80 percent of what's going on, you can probably make educated guesses as to where the boss is going awry. You might be able to tell when he isn't dealing well with politics, she says, or is not being assertive enough with new ideas. According to Susan Cramm, president of Valuedance, an executive coaching firm, if you're climbing the ladder toward an executive position you also need broad experience, across all functions of IT (and, preferably, across areas of the business as well). "I had a client who had only worked in infrastructure and he told me he wants to be the successor to his CIO. I told him: It's never going to happen," she says.

In addition to knowing all the angles of IT and the business, it helps to be a superstar or to possess the charismatic qualities that typically propel people into executive positions. One way to hone that reputation is to win awards, according to Shawn Banerji, an executive recruiter with Russell Reynolds. "Sometimes an award is legitimate and sometimes it isn't," he says. "But they show to the rest of the organization that a person has ambition."

3. Show you're a leader

Napoleon wouldn't have become emperor of France if he hadn't commanded loyalty from his troops, and the same is true in IT. To get support from the people you want to lead, don't say catty things behind your boss's back or promise anything you can't deliver yourself.

Instead, demonstrate the leadership qualities you know they desperately want to see from their manager, who consistently falls short. "You can learn a lot just by listening," says ZRG's Heller. "If the guy never makes it out of his office, then you should make the rounds," she says. "If the staff says he's all talk and no action, you want to make sure you're the guy who makes a promise and then follows through." Then, says Russell Reynolds's Banerji, they may begin to imagine what life would be like with you in charge.

When your boss takes a vacation or goes on a long business trip and you are put in charge, you have a golden opportunity to show how you would do the job. Heller suggests you might even ask your boss to give you an "acting" title while he or she is away — a subtle way to market yourself as a leader.

Just as you rally the troops in the trenches, you need to impress the other generals, too. If you are running a key project, then you should jump at the opportunity to speak at a budget or executive committee meeting where your project is on the agenda. If you can convey an executive presence, says Heller, they won't wonder what it would it be like if you were in charge. They'll already know.

4. Cultivate relationships with businesspeople

Establishing allies on the business staff can be tricky, especially at the highest levels. Talk about ousting a CIO with his C-level boss and you may get him fired. But you might fail to secure the CIO position for yourself because those same people you lobbied won't trust you.

Korn/Ferry's Rubenstrunk tells of a coup at a large, vertically integrated organization. The CIO had lost touch with the business and was frequently on the road. While he was gone, his lieutenant started meeting secretly with key executives over lunch and coffee. The lieutenant became instrumental in ousting his boss, says Rubenstrunk, but he didn't get the job because the executives didn't want such a blatant backstabber on their team.

A better tactic is to become indispensable. Volunteer for key projects — especially the ones nobody, including your boss, wants to touch. That will provide you with legitimate reasons to speak with businesspeople frequently, says Valuedance's Cramm. And it will give you an opportunity to shake any perception among business leaders that you're just a techie rather than a strategic business thinker. In fact, Cramm knows one IT lieutenant who missed his chance to become a CIO when he didn't sign up for a key project. When the CIO was fired, the company hired someone from outside.

In addition, don't bad-mouth your boss. Let the facts speak for themselves. If people try to bait you into talking about your inept superior, resist joining in, says Cramm. Instead, ask questions that allow them to vent their frustrations, and then provide context for their complaints. If someone asks you about a project your boss dropped the ball on, you can explain: "A lot of companies approach those kind of projects this way, but Joe decided to do it this way." If you appear objective, you'll be more credible, Cramm says.