Open ~/.zshrc
in your favorite editor and add the following content to the bottom.
# Git branch in prompt.
function parse_git_branch() {
git branch 2> /dev/null | sed -n -e 's/^\* \(.*\)/[\1]/p'
}
setopt PROMPT_SUBST
export PROMPT='%F{grey}%n%f %F{cyan}%~%f %F{green}$(parse_git_branch)%f %F{normal}$%f '