Using DBAN from USB drive

We are using DBAN to wide old computers, some no longer hace CD drives, here is how to install it on thumb drive:

• Step 1: Download DBAN (Darik's Boot and Nuke)'s ISO file from SourceForge.
• Step 2: Download Universal USB Installer from Pendrivelinux.com.
• Step 3: Run Command Prompt as administrator. You may be able to do the same thing with Disk Management. But in my case Disk Management refused to let me delete the volume of my flash disk.
  
  • Step 3.1: Type diskpart and hit enter. This runs the diskpart utility.
  • Step 3.2: Type list disk and hit enter. This lists all disks (including your flash drive).
    
    • Step 3.2.1: Look for your flash drive (look for its size) and keep note of its number.
  • Step 3.3: Type select disk # and hit enter, where # is number of your flash drive (see step 3.2.1). This selects your flash drive as the target to operate on.
    
    • Step 3.3.1: Type detail disk and hit enter. This lists the detail of the currently selected disk. Make sure it is your flash drive.
  • Step 3.4: Before you proceed, please ascertain that you have chosen the correct flash drive and have no desirable data on it. Type: clean and hit enter. This cleans the selected disk of its partition and format.
• Step 4: Run Disk Management. (You should be able to do the same thing with diskpart. But I have no advanced knowledge of diskpart so I prefer to use GUI whenever possible).
  
  • Step 4.1: Find your flash disk in the section below. It should have its entire space unallocated. Right click on the unallocated space and click "create new simple volume".
    
    • Step 4.1.1: In the wizard that appears, choose a volume smaller 2048MB. My knowledge is that a FAT-fomatted (FAT-16, to be specific) disk on Windows can hold a maximum of 4GB of data, with single file limited at 2GB. But since DBAN's ISO file is less than 20MB in size, there is no reason not to be safe. In my case I went with 512MB.
    • Step 4.1.2: Choose FAT as the file system.
• Step 5: Run Universal USB Installer.
  
  • Step 5.1: Choose DBAN among the lists of available options.
  • Step 5.2: Browse and select the previously downloaded DBAN ISO file as the source image.
  • Step 5.3: Select your flash drive as the burning target.
  • Step 5.4: Do not select the option that asks you if you want Universal USB Installer to format the flash drive for you.
• Step 6: Restart and boot into UEFI.
  
  • Step 6.1: In the boot order section, select the boot mode to be "Legacy" (it may be "BIOS" on your screen). This is the culprit that made my last attempt in the question fail. Apparently DBAN cannot be booted properly from UEFI.
    
    • Step 6.1.1: In some systems, instead of selecting between UEFI and BIOS boot modes in UEFI itself, you may need to boot into BIOS directly. Consult your motherboard/laptop manufacturers for instruction.

From superuser.com