If the device is visible in the Device Manager (do you know how to open this?) and is shown as RAW you have to initialize it, partition it, and format it. If it's shown as simply unallocated, you have to partition and format it.
Could you please provide the model number and, ideally, a link to the product page? Even with USB 3.0, and external SSD seems a bit odd. I'd be interested to see how they position it on the market. The best USB 3.0 sustained speeds I've ever seen myself are 102 GB/s write and 123 GB/s read. That's GibiBytes per second (
https://en.wikipedia.org/wiki/Gibibyte ), and pretty impressive for a USB "thumb drive."
@reedo: Maybe something like this http://www.samsung.com/global/business/semiconductor/minisite/SSD/us/html/portablessdt1/overview.html?gclid=CJfl5Jj8iscCFYSPHwodf9oJ-g, claiming 450 MB/s. I had a notebook at work with a hard drive, and the extract-from-repository, build, and unit test process took 20 minutes with my hdd and 12 on my USB 3.0 thumb drive. So if you want to carry your work around with you, it makes sense.