"Guardians of the West, Powers of Water, you who are emotions and pure love. Who is the morning dew, and the torrential rains, I call upon and invite your presence to witness this rite."
West can be represented with a blue candle.
Water is a strong force of nature. Our bodies are mostly water and we can not go very long without water or we will die. From conception until birth we live and breath a fluid filled environment. But once we are born fluid can take our lives, it can fill our lungs and steal our breath! A nice rain can cleanse the earth and wash away dust, but too much and it can flood. The balance of waters helps crops grow to feed our bodies and quench our thirsts.
To focus on the elemental associated with water I suggest seeing a tidal wave in your mind. Focus on it's sounds and the smell of the surf. Use your mind to force it to move how you want it to move, use your mind to reduce it down to a gentle ripple left by a stone cast into a pond, feel it wash over your body and feel it cleanse your soul. Imagine directing it from the tip of you athame like a stream from a hose and send it to the western quarter of you circle and ask it to remain there.