To sound more intelligent

Speak just a bit slower to allow yourself to select the most appropriate words and to give the impression of thoughtfullness.

To sound more powerful

Use short,simple declarative sentences. Say what you mean and mean what you say.Cut out any useless connectors, adjectives,adverbs and superlatives.

To sound more polished

Never answer a question with a blunt “yes” or “no”. Append a short phrase of clarification. For example,”No I did not see that” or “Yes, I know Mary”

To sound more articulate

Make a special effort to pronounce the final sound in a word and use its energy to carry over the following word. Pay special attention to final “t” and “ng”

To sound more confident

Carry your body up. Hold your head as if you had a crown on it.Do not let your arms and legs have a side-to-side-motion when you move. Keep your elbows and knees close to midline of your body

source : The Star,Friday 30 March 2007