how to using composer package for productsion level apps code example
Example 1: composer install production
composer install --no-dev --optimize-autoloader
Example 2: upgrade composer
To update composer command just find location of composer.phar and update as:
where composer #Retrieves you location of your composer.phar
cd path_to_composer.phar #Move to directory with composer.phar
php composer.phar self-update #Update your composer