Fill a large bowl with water and put something that floats in it, such as a cork. Meditate upon the water, feeling it's energy, it's Ki. Pick a direction and concentrate on swirling the water in this direction. Feel it swirling, growing stronger, moving faster.
Moving Water V.2
This is a harder version of water-moving. Put something in the water that sinks, such as a coin. Sit and meditate upon the water like before, and feel the energy of the water. Make a connection between the water and your hand, and move your hand upwards like you are holding something up. This will make the water pick up the coin. This will probably take lots of practice since it is not the nature of water to hold things up.
Hold your hands like you're making a Ki Ball. Reach out with your awareness and start pulling the moisture from the air into your hands. Remember, it's no different than moving water in a bowl. Don't be intimidated by the fact that you're moving water in the air. The first few times the air in your hands might just feel more damp, but as you become more and more powerful, it will become more and more obviously fluidic. At that point you'll probably need to use Psi, Ki, or some similar energy to keep it together since water doesn't naturally keep the shape of a ball.
Water Energy Fusion
This technique will fuse your Ki with the element of Water. For the first several times you will probably have to do this while in a meditative state. So begin by meditating. Open your eyes and look around and notice the Water in everything around you. Water is in you, it is in all things even in small amounts. Water is even in the air and if you concentrate on this you may begin to feel as if you are under the ocean. Breathe in, concentrating on the element of Water. Feel the Water filling you like Ki would fill you in a Ki Breathing tech. This will saturate your Ki with Water, creating Water Ki.
How long it will last depends on how well you perform this tech and how much Ki you expend. Assuming you do a good job with this tech and don't do much to use up Ki it should last between one and a half days to two whole days, during which it will slowly fade away. If you want to replenish it simply perform this tech again. If you need to get rid of it before then simply perform Ki Breathing a few times in order to flush out the Water Ki.
Water Ki is somewhat useful in attacks, but is much better for healing. It can be used to wash out toxins and to sooth anger.