Step 1: Items Needed
-A camera, one that has a shutter speed adjustment. Otherwise you are just photographing water all day and will not get the silky water effect. :0(
-If its windy, something to weigh down the tripod, such as one of those nifty sand bags you hook onto the underside of your tripod and load up with sand and rocks.
-A super steady hand or a remote control shutter trigger.
-A warm friendly personality
Step 2: Locate Some Moving Water.
Approach the body of water slowly, so as not to spook it.
Step 3: Befriend the Water.
Step 4: Do Not Ever Make This Face at the Water.
-Adjust that shutter speed! You want the shutter to stay closed for a few.
-Mess around with your F-stop's and ISO based on the natural lighting, your use of flash or not, etc. Auto will probably not help you in this case.
-Make certain the camera is on a tripod and stable, any slight movement of it when your shutter speed is slowed down can and most likely will cause your photo to turn into a blurry mess.
-If you are new to this and not an expert with a camera (Like me, still learning things about said camera) make sure you allow yourself plenty of time to do this so you can experiment and figure out the best settings to use when doing this.
-If you have a remote trigger, use it!! It is so much easier then using the one on your camera and risking camera shake!
Step 5: Another Important Note
Carry your camera and tripod in a case, one you can sling over your shoulder Indiana Jones style. This way you have your hands free while walking through possibly tough terrain.
Do not get too close to the water where you risk getting your camera wet unless you have some sort of waterproof covering over it!! Water is alot like a llama, it likes to spit at you when it has some especially intense rapids.
If on tough terrain, like hiking through the woods, bring a pocket first aid kit, wear some good shoes with traction and some clothes you don't mind getting dirty. Make sure someone knows where you are going and when you are expected back if going alone. So that way if you slip and hurt yourself or get yourself lost, someone will know where you are and can get some help to you (I'd say bring a phone, but cell phone reception is suckish in the woods sometimes.)
So that's all, Just practice practice practice and you too, can befriend the water into becoming friends with you so you can take some lovely photos of it without it getting angry.