Get enough private time and rest before you speak, and after if you feel tired then.
Introvert != shy
Introvert != stage fright
Introvert to me simply means I have a shorter energy supply when around people I don't know.
The closer they are to me, the more I can be around them without getting tired.
So don't equate introversion with social anxiety or inability to speak in public.
So with that said, learning public speaking for introverts should follow the same rules as for anyone else.
Unfortunately, people will interpret your comments according to their own biases, and I've that a lot of people are biased to distrust or dislike introverts. For this reason, I would never admit to being an introvert, in a business setting. I would rather tell people that I'm mildly extroverted, and then let them believe what they want.
Some hire an MBTI consultant for whole workshop days. Some just order a pre-made test.
"I have to be alone very often. I'd be quite happy if I spent from Saturday night until Monday morning alone in my apartment. That's how I refuel."
 to clarify to whom I'm agreeing.
No psychologist worth their salt would define an introvert that way.
a shy person.
Psychology. a person characterized by concern primarily with his or her own thoughts and feelings (opposed to extrovert ).
(edit: added "don't")
I mean, would you rather get invited to a party and spend 4 hours socializing with strangers, or give a talk at a conference for 1 hour? Guess it's different for each person but for me the party is worse.
But a clause needs to be added:
"If you have fear of public speaking and you want to overcome it"
The last part is crucial. Just because public speaking is temporarily in fashion in some business circles no more means we all have to do it than we all had to eat fondue in the '70's, or grow beards now (OK that's heading towards passéland). Public speaking is fine, but it's just one of thousands of human activities you may or may not wish to do. You might choose to learn to ride a motorcycle instead. Or leap off burning buildings. Whatever your thing is.
I would. Some people have crippling stage fright every time while several others would get it if the stakes are too high (imagine being called to demo at the iPhone launches). I doubt that the author being a natural public speaker can relate to that.
It's not about not being a good/polished public speaker but more about being so paralyzed with anxiety that your hands/knees shake and your voice breaks to the point that you couldn't read off a teleprompter. You lose all situational awareness and enter a fight or flight mode. If that describes you then take propranolol. (after asking your doctor of course)
You might feel good about your speech, but your audience might decide that maybe you shouldn't do that again.