Formatting USB drive with FAT32 using FreeBSD

Assuming your usb drive is /dev/da0

Using fdisk:

• Zero disk beginning with
  dd if=/dev/zero of=/dev/da0 bs=2m count=1
• Change first partition type to 12 (FAT32)
  fdisk -i /dev/da0
• Initialize fat32 file system
  newfs_msdos -F32 /dev/da0s1

Using gpart:

• List existing partitions
  gpart show da0
• Delete existing partitions
  gpart delete -i 1 da0
  1 being partition index, you might need to repeat this depending on output from gpart show
• destroy label after deleting all partitions (if you get complaints use gpart destroy -F to force destruction)
  gpart destroy da0
• create new mbr spanning entire disk
  gpart create -s mbr da0
• create new fat32 partition spanning entire disk
  gpart add -t fat32 da0
• Initialize fat32 file system
  newfs_msdos -F32 /dev/da0s1

However if you want GNOME to automount usb drive you shouldn't follow instructions above :-) Instead do this:

• Destroy disk labels with
  gpart destroy da0
  or zero disk beginning with (might not work in case of GPT)
  dd if=/dev/zero of=/dev/da0 bs=2m count=1
• Initialize fat32 file system on entire disk without using partition table
  newfs_msdos -F32 /dev/da0