(FORTUNE Magazine) – IF YOU'VE BEEN promoted recently to your first management job and if you got little or no training or preparation for it, you're not alone. Many employers, especially in these tight-fisted times, seem to believe that simply having watched your own bosses in action is enough to teach you how to be one. But as anyone who's been subjected to it knows, the sink-or-swim approach can too easily turn you into shark bait. "Most companies really don't do a very good job of supporting and developing new managers," observes Ben Dattner, a Ph.D. in organizational psychology who is head of Dattner Consulting (www.dattnerconsulting.com), based in New York City. Having coached plenty of newbies, Dattner has a few tips. First, he says, "assume you don't understand all that's required of you in this new role. It's complex, and if you go in thinking you 'get' all of it right away, you'll make a lot more mistakes than if you approach it as a learning process."

Likewise, he says, try to avoid the trap of assuming that other people are motivated by the same things as you are. "I coached one newly promoted manager who liked to have a step-by-step 'plan of attack' spelled out ahead of time for every action, but his team felt overwhelmed by all the detail," Dattner recalls. "He found that he had to adapt to their style and give them just the information they actually needed to know."

Perfectionism is another pothole. "Often new bosses are so intent on proving themselves that they push people to work late and come in on weekends to get everything perfect," says Dattner. "But is being a superhero really worth wrecking the work-life balance of the whole team? Be willing to back off a little."

What if, as so often happens, your former peers resent your new status as the Big Cheese and maybe even start dragging their feet? Notes Dattner: "People may stew for a while. Let them stew. But the work still has to get done, so you want to encourage both individual and collective accountability. Keep reiterating the consequences: 'Here's what will happen if we meet our goals, and here's what the negative results will be if we don't.' Use both the carrot and the stick to cultivate a sense of a shared fate." All leaders have to find ways to do it, so you may as well start now.

Don't ask for suggestions or opinions that you aren't seriously prepared to consider: "Send a clear signal about what's on the table and what's not. Some things are open to discussion and negotiation; other things, no. Be clear about which is which." Be clear, too, about the basis on which people will be rewarded. Discourage "in" and "out" groups. "People need to see equal opportunity based on performance, not on who likes you and supports you and who doesn't," Dattner says. "The less political your group is, the better you'll be able to navigate the politics outside the group in the rest of the organization." And that, friend, is where the really tricky part starts.