My book essential 2tb

Hi

I have just purchased this external hard drive in order to free up some space on my macbook 4.1 (white). The guy in the store told me it was a simple case of plug it in then drag and drop. It obviously isnt and know i am not sure what i have done and cant seem to find how to go back to the start. Could someone please advise me on what to do do? when i plug the drive in the icon is of a the drive with ausb symbol on it with a speedometer symbol next to it. In the guides i have seen it doesnt look like this? Also when i click into wd smartware the drive doesnt show up next to the mac analysis section. It did when i first plugged it in. Thanks in advance.

Can anyone help at all?