IMPORTANT!! Valet is a tool designed for macOS only.
brew updatein the terminal.
brew install homebrew/php/php71.
composer global require laravel/valet.
~/.composer/vendor/bindirectory to your system's "PATH" if it is not already there.
During the installation process, Valet installed DnsMasq. It also registered Valet's daemon to automatically launch when your system starts, so you don't need to run
valet start or
valet install every time you reboot your machine.