Pre-covid I used to do a bit of public speaking internally at work and sometimes at events on behalf of work.
Now I'm super rusty but have some opportunities coming up that'd also involve a technical talk component (which I have even less experience in).
What are some ways you've improved your public speaking as well as the quality of your presentations as a whole?
You can record yourself giving the presentation and go over the recording with a friend who has more public speaking experience. The recording will reveal areas where you can improve your body language or speech patterns.
practice! manufacture low-stakes ways to practice public speaking:
Recording yourself is a great solo-player tactic as Charlie mentioned, but as with many things in tech, you will get the greatest returns when you just try stuff. Present in low-stakes environments where it's impossible to fail (e.g. showing a small demo during daily standup) and move up to larger audiences as you become more confident.
On top of that, it really is just mentality. Public speaking is one of those things where you simply have to embrace your fear of failure and truly realize that even if you fail, you'll be okay. When you care less about something and put less pressure on yourself because of it, you will ironically do better at that thing. It's very similar to what I talk about with interviews.
For concrete tactics around preparation, check this out too: "How can I get more comfortable giving presentations in front of large groups?"