Well when using the energy of elements you must remember, it will not give you their power, it will let you use their energy. Havesting the energy of an element is like harvesting the energy from the universe in rituals/spell work.
As you know energy is in everything, including us, this energy we can "barrow" from the universe, and other things. Learning how to do so isn't hard, but it isn't necessarily easy. So if you don't know how to use your own energy or will it, then I suggest you study how to do that, because it will help you in learning how to "barrow" the energy of elements.
If you want more information please read AwakeTooLong's "The Basics: Expanded".