How do I update zsh to the latest version?

If you have Homebrew installed, you can do this.

# check the zsh info
brew info zsh

# install zsh
brew install --without-etcdir zsh

# add shell path
sudo vim /etc/shells

# add the following line into the very end of the file(/etc/shells)
/usr/local/bin/zsh

# change default shell
chsh -s /usr/local/bin/zsh

Hope it helps, thanks.

If you're using oh-my-zsh

Type omz update in the terminal

Note: upgrade_oh_my_zsh is deprecated