Installation/Debian/Wheezy
Enable Backports
Please read and follow Debians instructions if you haven't enabled the backports already.
Install packages
As root run:
apt-get install build-essential openssl libssl-dev libcurl4-openssl-dev graphicsmagick-imagemagick-compat graphicsmagick-libmagick-dev-compat git-core
apt-get -t squeeze-backports install redis-server