install to ~/zsh-custom/theme/owiewestside.zsh-theme
and add
ZSH_THEME="owiewestside"
to your ~/.zshrc
Just run this...
$ mkdir -p .zsh-custom/themes
$ curl -o ~/.zsh-custom/themes/owiewestside.zsh-theme https://raw.githubusercontent.com/owenstranathan/owiewestside.zsh-theme/master/owiewestside.zsh-theme
then add:
ZSH_THEME="owiewestside"
to your ~/.zshrc