If your fly is catching on your flyline or leader you are casting tailing loops--a very common casting error. It's primary cause is starting your forward cast too hard and fast. To correct the tailing loop try this--start your forward cast slowly and then accelerate to quick stop at the end of the forward cast. While the change may seem subtle the difference in the cast will be huge.

If you fly line lands in a clump of pasta in front of you and probably well short of your intended target, you are probably either starting your forward cast too soon or dropping your rod tip too far down on the back cast--or both. The best way I have found to correct both of these errors is to WATCH THE BACK CAST. The back cast is usually out of sight and therefore, out of mind. Turn you head and watch the back cast. Modify your back cast to do two things. Hesitate on the back cast long enough to see the line completely straighten out in back before you start forward. Don't let your rod tip drop too far towards the water--while I reject the conventional wisdom of keeping the rod between 10 and 2 o'clock (like Lefty Kreh says: you don't cast with a clock)--But swinging the rod almost to the water is going to put your line on the water behing you. Think about the back cast being UP and back. In fact, your casting hand should travel up a ramp as you move it backwards. Put the butt or the rod under your shirtsleeve if you can't stop your rod from traveling too far down on the backcast.

Remember: it's tough to fix something you can't see, so turn your head and WATCH the backcast.