As a starting point, it is a good idea to get feedback on your speaking habits.
How audible are you?
Are you doing anything distracting? E.g. moving hands a lot, pointing, or rotating body too much.
Are you using certain ‘fillers’ repeatedly? E.g. ‘...and like’, ‘Look, I mean’, ‘Uhmmm’
Where are your eyes going? Are you making eye contact? With just one person or the whole room?
Tone of voice
Are you changing the pitch of your voice depending on the content?
Waving/reading off notes
If you are holding notes, what are you doing with them? What are you doing with your hands?
How are you standing? Where are your arms? What are you doing with your legs?
Are you taking natural pauses to breathe?
Speed of talking
Is it easy to follow the speed at which you are talking?
Passion, purpose, positivity
What is your general demeanour like when talking?