1. Auto Suggestion
# install via homebrew
brew install zsh-autosuggestions
# add the following at the end of .zshrc
/usr/local/share/zsh-autosuggestions/zsh-autosuggestions.zsh
# force reload .zshrc
source ~/.zshrc
2. Syntax Highlighting
# install via homebrew
brew install zsh-syntax-highlighting
# add the following at the end of .zshrc
/usr/local/share/zsh-syntax-highlighting/zsh-syntax-highlighting.zsh
# force reload .zshrc
source ~/.zshrc