Install with curl:
sh -c "$(curl -fsSL https://raw.githubusercontent.com/robbyrussell/oh-my-zsh/master/tools/install.sh)"
Download zsh-autosuggestions:
git clone https://github.com/zsh-users/zsh-autosuggestions.git $ZSH_CUSTOM/plugins/zsh-autosuggestions
Download zsh-syntax-highlighting:
git clone https://github.com/zsh-users/zsh-syntax-highlighting.git $ZSH_CUSTOM/plugins/zsh-syntax-highlighting
In ~/.zshrc
change plugins to add zsh-autosuggestions zsh-syntax-highlighting
to look something like this:
plugins=(git zsh-autosuggestions zsh-syntax-highlighting)
Reopen terminal