do you have another computer? if not then you would need a device like this - http://www.newegg.com/Product/Product.aspx?Item=N82E16812232002
once the drive is connected, you run a software program like this - http://disk-imaging-software-review.toptenreviews.com/acronis-true-image-review.html
follow the instructions and it makes an exact copy of the contents on drive A to drive B. The catch (and this is why I asked you how big the HDD was) is that drive B needs to be at least the same size as drive A, if not larger, for it to work.
here's a list of the top software available... http://disk-imaging-software-review.toptenreviews.com/