How to replace the negative battery cable?

Can I ask which one? There are two, one by the battery and the other is under the car near the engine. In either case they are not that bad to change out, here is how to, here is how to change out the positive cable power point so you can see what you are in for but if you upload an image of what you are talking about, I can help step by step. Check out the images (below). Please let us know what happens.