Open TERMINAL and go for root (super user), type the commands bellow :
Go for below command for inserting new repositories from RPMFUSION, the place where CAIRO-DOCK is:
rpm -ivh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm
And GO FOR IT, install the dock by typing below command :
yum install cairo-dock\*
ENJOY your DOCK !!!!!