From Fedora Project Wiki

  1. Ensure only the single target device you prepared is selected as the installation target disk.
  2. Ensure the Advanced Custom (Blivet-GUI) option is selected under Storage Configuration, and complete this screen.
  3. On the BLIVET GUI PARTITIONING screen, delete all existing partitions (if any).
  4. Create any necessary bootloader partitions (e.g. EFI System Partition for UEFI installs, BIOS Boot partition for BIOS installs onto a GPT disk, PReP boot partition for PowerPC installs).