make old mp3-player into a bootable drive

The title says it all, this is what I'm trying to do. Just deleted all the data and did the following:

sudo fdisk /dev/sdc --> create primary part. Nr.1 within default range of sectors (whole USB drive)

sudo mkfs.ext3 -c /dev/sdc1

But now when I try to run the Startup Disk Creator it gives me the following: "Startup disk creator: Failed to install the bootloader". What now? Do I have to set permissions on the /dev/sdc differently?