Installing Particle\Validator is very easy, if you're using composer. If you haven't done so, install composer, and use composer require to install Particle\Validator.
curl -sS https://getcomposer.org/installer | php php composer.phar require particle/validator
Make sure you include
vendor/autoload.php in your application, and then create your first validator
use Particle\Validator\Validator; $validator = new Validator; $validator->required('first_name')->lengthBetween(0, 20); $validator->optional('age')->integer();