To install URLify, you can add it as a dependency by downloading Composer, the PHP package manager.

`$ curl -s http://getcomposer.org/installer | php`

Then run this command to install Composer:

`$ php composer.phar install`

For more details, see https://getcomposer.org/

Then run this command to install the URLify library:

`$ composer require jbroadway/urlify`