How to Upgrade Fedora 30 to Fedora 31

Prerequisite

$ cat /etc/fedora-release 
Fedora release 30 (Thirty)

Update software and back up your system.

$ sudo dnf upgrade --refresh

Install the DNF plugin.

$ sudo dnf install dnf-plugin-system-upgrade

Start the update with DNF.

$ sudo dnf system-upgrade download --releasever=31

Reboot and upgrade.

$ sudo dnf system-upgrade reboot