Hydro = Water. Kinesis means to control an object or substance with your mind; no physical contact nor technology. Hydrokinesis means to move water with your mind, no touching the water nor using technology. Through hydrokinesis you can control water, that is what hydrokinesis is about.
Not to be confused with hydro mancy which is a form of divination in which the diviner uses water to divine.
I had a lesson copied down somewhere, but I'm not sure where it is now. I also don't really have time to come up with a new one and teach you right now. So, send me a message if you can not find a teacher by the 11th of this month and if you are still interested in learning Hydrokinesis. Until then here are my tips for you:
1) Practice often.
2) Remain confident, no matter what.
3) Try different ways of performing the same task then try those ways that work best for you to perform different tasks. Through this you may find a method that works better for you then the one you are given.
Here's a quick lesson to help get you started, too.
Put a toothpick in a sink/tub full of water(got this bit of the practice from somebody else, the rest is my own stuff) then visualize with your mind a current in the water moving the toothpick. Place your hands just above the water or just below it's surface and continue visualizing the toothpick being moved by a current of water. Visualize the current itself moving through the tub/sink to move the toothpick. You can also do this while you are in the tub if you want to take a bath, but however you choose to do it do not move the water with your hands. If you hold your hands just above the water then moving your hands in the direction you want the current to go(without actually touching the water) may help you get started, that's what I did at first.