I have found that I barely ever, if ever, lie. I think part of me just isn't really capable of it. There have been a few times of course but for the most part I am an exceptionally honest person. I don't try and hide things either. It just sorta happens. I have to say that I highly encourage this as it comes with a number of perks. There's at least one anyway.
People will believe anything you say.
If you've ever had a really strange situation happen that sounds like a totally stupid and made up excuse, then people will buy it. Excuses sound like excuses, and always will. If you've never given anyone reason to doubt what you say though, then there's a very very good chance they'll believe you. Remember that one time your dog really DID eat your homework? Then it puked it out and your cat ate it? No teacher would believe that unless you were already totally honest and up front about things before. Not that I ever did my homework. At least I told my teachers outright that I never did it. They didn't like me for that.
Seriously, be honest. It generally is the best policy.