First, we need to partition our disk. Here, we're going to create two partitions of half the disk each.
Start by using fdisk against /dev/sdb:
$ fdisk /dev/sdb
You'll be dropped into a different shell, that of fdisk.
First, we will create GPT disklabel by typing g:
Command (m for help): gBuilding a new GPT disklabel (GUID: DE706D04-7069-456C-B8C4-C3E405D18A06)
Next, we will create a new partition, with a partition number of 1, a first sector of 2048, and of the size 1 GB.
We do this by pressing n and Enter, accepting the defaults of the first two prompts (by pressing Enter without input) and typing +1G when prompted for Last sector:
Command (m for help): nPartition number (1-128, default 1): First sector (2048-4194270, default ...
