Sara B. answered 05/04/22
Public Speaker 20+ years, expertise in presentations & job interviews
I would think it would be similar to the way you developed confidence for getting better at other things you had little to no experience doing at first. Experience and feedback seem to grow confidence. Speak about topics that you know well. Challenge yourself to speak in environments where you are already familiar with the audience, such as school, church, book clubs, etc. Aim to speak continuously such as weekly or ideally more often. It can be a short speech at first, perhaps 1-3 minutes.