sudo add-apt-repository ppa:ondrej/php5-5.6 -y
sudo apt-get update
sudo apt-get install php5-fpm -y(Update) For Debian Wheezy
echo "deb http://packages.dotdeb.org wheezy-php56 all" >> /etc/apt/sources.list.d/dotdeb.list
echo "deb-src http://packages.dotdeb.org wheezy-php56 all" >> /etc/apt/sources.list.d/dotdeb.list
wget http://www.dotdeb.org/dotdeb.gpg -O- | apt-key add –
sudo apt-get update
apt-get install php5-cli php5-fpm ….. (or whatever package you might need)