On Cnet there is a very informative article about how to easily root your android phone. The article warns against rooting phones without knowing what can happen and I tend to agree. You will void your contract if you root your phone. However, if you are determined to root your android phone. The directions are very clear. The article also mentions needing to use a free Windows Utility called Kingo Android Root and following the 3-4 basic steps included in the article.
I cannot stress enough that rooting any phone or android device if done incorrectly will void your contract with your service provider and can render your phone unusable if you do not know what you are doing.
Here is a link to the exact article http://www.cnet.com/how-to/how-to-easily-root-an-android-device/
There are plenty of other articles which will explain the dangers of rooting an android phone or device.
I hope this helps.