A common technique your opponent may use in a deposition, particularly if he is older or more experienced than you, is to rattle your concentration with obnoxious behavior such as improper objections, loud sighs, rattling of a newspaper, etc. I have found that an equally effective defense to this technique is to completely ignore the obnoxious behavior. Focus on the deponent and your game plan and refuse the opposing lawyer's invitation to be drawn into an argument. In fact, you should simply pretend he's not there, unless he makes an objection to one of your questions that is worthy of your consideration.
The obnoxious behavior I've described may pose ethical issues to be considered on another day. In the meantime, however, consider this hypothetical, based on a true story: You are defending a deposition that is being conducted by someone more experienced than you who has not learned the importance of ignoring the other side. Even though you are less experienced, you are well aware of your opponent's weakness. You also know that if you object in just the right tone of voice, and do it just a couple of times, he will explode with anger, making it difficult for him to stay on track for the rest of the deposition.
If you can make the other lawyer angry, you will thwart his deposition goals. Would it be ethically proper to adopt the magical anger-inducing tone of voice in making proper objections?