1. Take note of your body language while saying no to someone. Are you smiling? Nodding? Using positive body language may give a conflicting message and weaken the impact of what you're trying to say.
2. Avoid encouraging the speaker by asking questions that might indicate that you're interested (such as "Does it really have to be by this afternoon?").
3. Don't be afraid to interrupt the speaker. Passively listening without giving any signs that you object may indicate that you're willing to go along with whatever it is they would like you to do, and reinforce their confidence in asking you. Say something like, "I'm very sorry; I'm going to interrupt you…"
4. If someone approaches your desk and you want to appear more in charge, simply stand up. Standing puts you at eye level and creates a psychological advantage.
5. Meetings are also a great place to get stuck with extra work that you simply don't have time for, so starting off by saying to your colleagues that you have no room left on your plate for extra projects pre-empts any ideas they might have had.
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