What body language expressions I can use to show more confidence during public speech?

Body language is a type of non-verbal communication in which physical behavior, as opposed to words, are used to express or convey information There are three maintypes of body language: eye contact.bodyposition. gesture and movement Here are some tips to help ensure your body language works for, and not against, you: Prep with a power pose.Dial up your energy level.When the going gets tough, start smiling.Play supermodel to reduce conflict.Don't gesture above your shoulders.Talk more with your hands.Use props to engage

Just go with the flow during your speech which means if you need to use hand gesture to express yourself then do it. Audience might feel awkward if you stand in front of them and giving speech in a monotonous tone of voice. they might think that you are reading your speech rather than emphasizing it word for word. using hand gesture you will feel more relaxed and at the same time your tone of voice will change and it will sound more confident than you can never imagine. 

Just be yourself. Any alteration in behaviour pattern will lead to anticipation of faking the interview.

Just have control on the content what you speak. Answer only what is needed. Too much of over information might lead the discussion to some other angel. 

You can show them the way you speak without any voice trembling...hand gestures... smiling... and of course having an Eye contact towards your audiences in this way they can see, they can sense, and they will listen to your speech... they can be inside yourself if u will show an eye contact because it is a sign that u are honest and sincere in whatever you are pointing out.

First of all I should to stand before the public confidently. And control the facial expressions . the voice should not too low nor too hight it should be in medium level . the dressing should be decent but not shovey