I would use parted instead of fdisk.
first do check what kind of partition table you actually created. EDIT: Yes fdisk supports gpt disk lables
$ sudo <device file> print check for : Partition Table: gpt
If needed create a gpt partition table
$ sudo parted <device file> mklabel gpt Then create a new partition
$ sudo parted <device file> mkpart primary <filesystem> 0% 100% After that you can create a new filessystem onto partition
$ sudo mkfs.<filesystem> <device file> Documentation for Parted: GNU Parted
Documentation for mkfs (not filesystem specific): man mkfs