There are thousands of resources out there that tell you how to be a great trainer. But have you ever thought, "Just tell me what not to do?"

Here are some of the big no-no's. For a more complete list, see Michelle Baker's blog, phase(two)learning.

You're unprepared. Adults can see right through a flimsy layer of knowledge, even if they're new to the subject matter. If you've been asked to teach content on which you're not an expert, be sure to research it thoroughly before you face your learners.

The only body part moving is your jaw. Nerves can result in an unnatural stiffness while presenting. You don't have to constantly pace the room or make wild hand gestures, but move the way you would if you were speaking emphatically to a friend. The best way to accomplish this? Practice your delivery over and over again.

You're too energetic. Opposite the stiff trainer is the one who leaps around the room and talks too loud. If you're naturally exuberant, you might want to limit your caffeine intake before class.

You can't manage. Difficult participants, that is. Learn classroom management techniques to control participants who are disruptive to your session.

You're a know-it-all. Your learners' minds aren't content-dumps. Learners have skills, experience, and knowledge too. Let them arrive at conclusions themselves, through interactive discussions or action-learning activities.

You just want to play. Gamification is the thing right now. But if your content doesn't lend itself to games, don't force it. And be mindful of your audience—they may not take kindly to silly games, or games that put them on the spot.

The session's over, but you're still talking. End on time. Just stop. See how easy it is?