You asked

How do I talk to my son about puberty?

Whether you or your partner decides to talk to your son about puberty, the important thing is that you do talk to him.  The first thing is to make sure he understands that changes are normal for every boy and that everyone his age will go through them at some stage. Puberty can cause feelings of insecurity and anxiety , so make sure you’re reassuring and that you’re open to questions during your conversation with your son.
Use anatomically correct language when talking to your son about puberty. Using euphemisms will only serve to embarrass him. If you can’t refrain from using euphemisms, get someone else to talk to him about puberty.
You should be as specific as you can possibly manage. Inform him that his voice will break as it changes and his penis and testicles will increase in size. You should also explain that wet dreams may occur.  You should also explain how he will need to be extra vigilant about hygiene.
You should be prepared to push your embarrassment to the back of your mind and answer some very tough questions. Your son may want to know why he doesn’t have pubic hair yet.
It’s a good idea to give your child a book that he can refer back to. Buy a book that contains all the correct facts. Why not try, “What’s happening to me? Boy”, by Alex Frith or “Puberty boy”, by Geoff Price.
Boys will generally feel a little more comfortable talking about their bodies with other males so if possible your partner or another trusted male should do the talking.

More questions

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Puberty can be a source of insecurity and worry, so make sure you’re reassuring and that you’re open to questions during your conversation with your son.
For boys, puberty starts when the brain sends a signal to the testicles to produce testosterone
This is the time where children begin the journey from kids to adults. It’s a long journey, one that can be anxious, exciting, difficult and challenging all in one.
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