1. Dual-boot or triple-boot your system.
Install multiple Operating System (OS) in your system. Preferable different GNU/Linux distros. For example a stable Fedora F21 and Fedora Rawhide (F22). If you're dual-booting between Windows and GNU/Linux, make sure you pick the common file system such as ext2/3/4, there are quite a few software exists that can let you access your GNU/Linux partition like Ext2Fsd, Linux Reader, or Ext2Read. If you intend to use block device encryption as in Linux Unified Key Setup (LUKS), you can try DoxBox.
There are a few incidents after upgrading to the latest kernel, I can't login through the graphical user interface or X. Hence, you're stuck in the console. The best way is to wait for a few days (which is why you should dual-boot to use other distros or OS) for any updates or fixes. Boot up the system but login through different terminal using the keyboard short fo Crtl-Alt-Fn keys. Run the yum update through the console and you should be able to boot up. Or you can boot up using the last working kernel version, you can see that in GNU Grub bootloader, which is likely to work.
The console tool to manage NetworkManager. Setting up Wifi in console used to be quite troublesome, but since the release of nmcli, we have far more easier tool to manage our wireless connection. This is so true when you've to switch to different terminal to update your distribution without using at LAN cable. See 2. Example of usages shown below.
Check available Wifi connections. Yes, that is a bar graph in the console. Awesome, right?
$ nmcli dev wifi list * SSID MODE CHAN RATE SIGNAL BARS SECURITY * AAA Infra 2 54 Mbit/s 74 ▂▄▆_ WPA1 WPA2 BBB Infra 2 54 Mbit/s 20 ▂___ WPA1 WPA2 CCC Infra 1 54 Mbit/s 35 ▂▄__ WPA2
To make a Wifi connection. To prevent the Bash shell from saving your password in the history, prepend an extra space before the command.
!----- extra space v $ nmcli dev wifi connect AAA password Device 'wlp3s0' successfully activated with 'bx12345e-x2w3-112z-kk33-e348f22345qa'.
4. Recovery Disk
If you don't dual-boot with different GNU/Linux distros. Use a recovery Live CD or USB. Find the extra unused thumb drive and install in it. If you save you a lot of time especially when there is disaster like hard disc failure and you have to wait to download a full Live CD.
Conclusion. If you want to try the unstable GNU/Linux early release, be prepared for breakage and constant restarts. Do remember to backup daily. Or you can switch to a rolling-release distro like ArchLinux, where packages are continually updated instead of re-installation.