Got a new ipod, how do you transfer music from the old one to the new one?

You don't. At least not directly.

You can either sync the music from a computer onto the new iPod like you did with the old one, or in the case of purchased music download it from the purchased section of the iTunes Store on the new iPod.

See here: Redownload apps, music, movies, TV shows, and books - Apple Support

and here: Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support