The presenter should be looking at every face in the audience,
not talking over their heads or out of the windows, or intoning
in the upper left-hand corner of the room.

Hand gesture will send clear, powerful visual message into the
other unconscious audiences.

The recommended position of the feet is (for men) the heels
from 20 to 25 cm parts, for (women) the heels about 10 cm
parts, with the toes pointing out slightly, making a 'V' shape.

It is advised to talk TO and not AT the audience.

Eradicate off putting habits. Scratchiness, rubbings playing
with fringe, etc., are unacceptable.

Watch the listeners' reactions. Adjust the speech pace and
explanation to environment.

Never turn your back on your listeners. It's rude and in any
event can lose control of the audience when fail to face them
directly.