Basic Casting Tips
The beginning angler can often be a danger to himself and others nearby if he doesn’t know how to cast his line properly. No one wants to spend most of that dreamed about fishing trip extricating the hook from someone's hat or ear, especially his own. So it's a wise move to do some casting practice on the back lawn before you go.
You don't need to use lures or live bait, but to keep the weight true to what you will be using on that day, try some small pieces of thin cord or shoelace. The main principle to remember is that the fly will follow the direction that the tip of your rod was going when it was suddenly stopped. It follows then, that the tip of the rod must not be lowered from the target line.
While this sounds easy, there are many factors involved that can cause this to happen. Good casting is like a good golf swing. You need to use your whole body. So if your cast goes awry, you may find you've inadvertently lowered your hand or your shoulders as you cast. It's important to keep in sync with your body's rotation so that you can lead with your elbow for the forward move.
Another reason for problems with casting is holding the rod hand too low. Watch the position of your feet also. If your back foot is too far out and back, it will prevent you from making that abrupt stop so necessary for a long back cast.
If you find during your practice that there isn’t enough power to maintain the correct trajectory, it could be that you've cast too hard on the forward movement. This will cause slack in the line due to the fly pulling it down too hard. To correct this, accelerate faster on the back cast.
If you are a complete novice, it could be a wise move to get some training from an expert. Or you could download a video on the matter from the Internet, where you'll find many such offers. At the very least, you'll need to watch some pros in action so you can have a reasonable chance of copying their actions.
Many fishing guides and trips also include training in their package, so it might be worthwhile to go on one of these to get expert tuition right from the first. It will stand you in good stead for the rest of your life.