Options to create a single full-disk partition on /dev/sdb
fdisk /dev/sdb
Command (m for help): p

Disk /dev/sdb: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005a9b9

  Device Boot      Start         End      Blocks   Id  System

Command (m for help): n
Command action
  e   extended
  p   primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-30401, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-30401, default 30401):
Using default value 30401

Command (m for help): p

Disk /dev/sdb: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0005a9b9

  Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1       30401   244196001   83  Linux

Command (m for help): w
Format it as ext4
mkfs.ext4 /dev/sdb1