How to setup Virtualbox guest additions on Fedora 20

Fedora 20 (Heisenbug) is currently the latest release and if you want to try it on VirtualBox then install the guest additions for full functionality.
Installation is simple and takes a few steps, but involves download and updates which would require some bandwidth.
1. Update Fedora
The first thing to do is to upgrade all packages and make the system uptodate.
$ sudo yum distro-sync
2. Install kernel headers and build tools
VirtualBox guest additions are always compiled so they need necessary build tools and kernel libraries. Install them with the following command.
$ yum -y install kernel-devel kernel-headers dkms gcc gcc-c++
Reboot
After upgrading and installing kernel headers, reboot the system.
3. Compile virtualbox guest additions
Click on Devices > Insert guest additions CD image on the VirtualBox window menu.
The cd image is now available in fedora at /dev/cdrom or /dev/sr0.
Create a directory at home and mount the cd in it.
$ mkdir vboxcd
$ sudo mount /dev/cdrom ~/vboxcd
password for silver:
mount: /dev/sr0 is write-protected, mounting read-only
$ ls
32Bit cert VBoxSolarisAdditions.pkg
64Bit OS2...

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How to setup Virtualbox guest additions on Fedora 20