There are many aspects to being a good liar. You have to know what to say, when to say it, how to say it and most of all, how to not get caught. Let us start back before the lie is even told. The first thing you need to know is what you're going to say and how you're going to say it. You don't want to come up with something during the spur of the moment and have what you're going to say come out with a bunch of “ummm(s)” and “uhhhhh(s)”.
Once you know what you're going to say, you need to know how to say it. You can't be sounding like a robot when you're speaking. Treat it as acting. Put some emotion into it. If you're lying about being sick, talk like your nose is stuffed up, or if you get a chance beforehand, tickle the back of your throat with your toothbrush (don't make yourself get sick). It should bother your gag reflexes enough to make your eyes water.
The third rule about being a good liar is to not get your stories mixed up. I've seen this cause lots of problems in my day. Also, never change your story. If you tell it somebody one way, you better make sure you tell it the same way to the next person.
Last but not least, if you're going to lie to somebody, do it alone. Don't drag anyone else into it with you. This could either cause them to get hurt or in trouble, or they could let the cat out of the bag on you at any point in time. Also, don't lie to somebody if the consequences could get somebody hurt whether it be emotionally or physically. The truth is though, a little white lie never hurt anyone.
