Richard Hughes is packaging up GNOME 3.12 in a copr repo for people running Fedora 20. Note that this repo is contains software that is in development, and thus should be considered experimental.
Before enabling this, be sure to check the copr repo page for any further information about installing and using this repo
To enable the repo, create a new repo file in /etc/yum.repos.d/
:
sudo touch /etc/yum.repos.d/rhughes-f20-gnome-3-12.repo
Next, edit the file (again as root) and paste the follo the following repo definition:
[rhughes-f20-gnome-3-12-i386]
name=Copr repo for f20-gnome-3-12 owned by rhughes (i386)
baseurl=http://copr-be.cloud.fedoraproject.org/results/rhughes/f20-gnome-3-12/fedora-$releasever-i386/
skip_if_unavailable=True
gpgcheck=0
cost=900
enabled=1
[rhughes-f20-gnome-3-12-x86_64]
name=Copr repo for f20-gnome-3-12 owned by rhughes (x86_64)
baseurl=http://copr-be.cloud.fedoraproject.org/results/rhughes/f20-gnome-3-12/fedora-$releasever-x86_64/
skip_if_unavailable=True
gpgcheck=0
cost=800
enabled=1
Exit your text editor, and update your system with
sudo yum update
Finally, reboot your system, and you should be running fedora 20 with all the GNOME 3.12 goodness.