The key to Elemental Witchcraft is understanting those energies.I am going to give here some general characteristics of these energies,however, every person has a different,unique perception of these energies so you must find that for yourself.How to do that?You need to create a connection between you and those energies by meditating and focusing on the effect that the physical manifestation of each element has on your spirit.This means that when you sit by a fire (that is the size of a bonfire or bigger so that it'll burn for some time)
what thoughts enter your mind?What kind of memories and feelings do you get?When you lie down on the earth with your skin touching the soil or the rocks,when you are floating on the water or sitting on a windswept hill,what do you feel?After you do the above a couple times you will start feeling the energies that cause everything you feel.Then you need to let those energies flow through you and gradually start to control their flow inside your body.Once you can do this easily then you will be able to extract elemental energies to help you in your spellcasting.
Air Element Energy:
Air is the element of thought,freedom and mental activity.Its energies are in constant motion and stimulate memory and overall mental activities.This type of energy is used in spells that:help memory and/or inspiration,give you clear thinking over a situation,help free your mind from anything that may bind it(negative emotions,obsessions,etc).
Fire Element Energy:
Fire is the element of action,will,healing and destruction.Its energies are also in constant motion but in a more fierce kind of motion (it is rather hard to explain the differences,you need to feel them).This type of energy is used in spells that:influence emotions such as love and hatred,make new beginnings,warm a cold heart and aid in some types of curses.
Earth Element Energy:
Earth is the element of stability,fertility,protection and balance.Its energies are stable and firm giving a feeling of balance.This type of energy is used in spells that:grant protection and/or fertility,stabilize or slow down a situation,bring balance in the life of a person and money spells.
Water Element Energy:
Water is the element of emotion,healing and cleansing.Its energies are fluid which means that they can either be stable or in motion and give a sensation of purity.This type of energy is used in spells that:stimulate the emotions of a person and help that person express them,heal the heart from pain, sadness,anger,etc and cleanse negativity from a space or a person.
There can be other uses in spells for these elements,but that depends on the situation that calls for the spell.The text above is mine.Information was taken from the following books:
David Rankine and Sorita D?Este-Practical Elemental Magick
Earth, Air, Fire & Water Techniques of Natural Magic-Scott Cunningham