It is easy to overlook the relevance of a well-presented appearance. But those who dismiss the significance a physically powerful image do so at the own peril. The key is to chose a look appropriate to the audience. Try to reflect the style of those with whom you are communicating. Use your commonsense over what suits a relaxed image for a small workshop and what works for a  more formal approach to  a large gathering. Choose an image which aligns with your own character and develop body language that expresses your stature and influence. A well pruned and tended tree always bear the best and the most fruit.