Unable to upload any media from desktop

I downloaded WordPress yesterday so I am completely new to it and therefore I don’t understand any of the jargon based answers which were solved in previous posts.

Whenever I attempt to upload an image I receive this error:
Unable to create directory wp-content/uploads/2013/07. Is its parent directory writable by the server?

I attempted to find an IUSR in the security tab (in folder properties on windows 7) since apparently it can be the cause of the problem, but the explanation was targeted to experienced users and therefore it didn’t aid me in finding a solution.

If anyone is able to help me with this problem; it would be greatly appreciated, but if you do have a solution could you please write it out in a step-by-step method since I won’t be able to solve it if someone just throws some .php jargon in a post or something.

Thanks Again.