Diskpart

Run CMD.EXE as administrator
Type following commands and hit ENTER key after each command.

DISKPART                      - Starts DiskPart (duh)
LIST DISK                     - Shows numbers assigned to disks
                                Note the number assigned to drive you want to use
                                I'll use number 2 in this example
SELECT DISK 2                 - Does this really need an explanation?
DETAIL DISK                   - Optional step to make sure you picked the right drive
CLEAN                         - The first & last 1MB of the drive will be overwritten with zeros
                                Alternatively, use "CLEAN ALL" to overwrite the entire drive (takes forever)
CONVERT MBR                   - Converts the drive from GPT to MBR (or vice versa ; optional)
CREATE PARTITION PRIMARY      - Create a primary partition on the drive
FORMAT FS=NTFS QUICK          - Format the partition as NTFS using quick format. Alternatively FS=FAT32
ACTIVE                        - The partition can contain OS startup files
ASSIGN                        - The next available letter is assigned to the drive
                                Alternatively you can manually assign one by adding "LETTER=X"
EXIT                          - Exit from the DISKPART program
EXIT                          - Exit from the command prompt