The Backlash, the birds nest, over running. It goes by many names and is one of the more common problems faced by anglers. Everything from a small twist or knot all the way up to something that looks like you need a brushhog to take it out. It is not a matter of if, it is in fact a matter of when. It doesn't matter if your a novice just getting into the love of fishing or a professional angler like myself, you will run across this problem several times during your life as a fisherman. Each time you stop to fix it, you lose daylight and precious time in a tournament situation. A little bit of prevention and practice go along way in the field.
In order to understand how to avoid a backlash, you must first understand exactly what causes them. There are actually a number of contributing factors, but the keys are the Brake and drag settings and thumb control of the spool. You see, what is happening when a backlash occurs is the spool spins faster than the line can be released from the spool casing. This causes multiple rotations of line to bundle within the spool casing and can catch, tangle, and twist(ultimately weakening your line each time).
As with any process involved in fishing, more experienced anglers will have fewer mistakes than novice angler. However, they are in no way immune. What the more experienced anglers have done is understand what speeds work best for a particular line, and the line does make a difference. Lines with rough textures create more drag through the control eye and low the speed of the line through it.
The other thing, which I think really has more effect on this is thumb control. This is where practice and muscle memory come into play. Having a looser brake/drag setting allows for smoother casting many anglers rely on thumb control to maintain their casting and prevent birds nests. Take you rod and real set up out into your back yard or porch and practice casting with a plug. Start with proper overhand technique and vary the pressure you put on the spool with your thumb while allowing the spool and line to move smoothly. Be sure not to stop to spool abruptly. This can cause the bait and line to jerk back in your direction slightly and can cause a larger splash and spook the fish. Once you think you have mastered this with proper over hand technique you can then move on to practicing with other casting motions you normally use.
One final thing is reel maintenance. Make sure you keep you spool oiled so that it does not catch or rust with in the casing. If you don't this could cause the spools speed to become irregular during casting. A little bit or Reel Magic every now and then will take care of this. I keep a can handy on my boat at all times.
Practice and it will save you time and headaches in the field.