That sounds more like a life lesson than a career lesson but this industry is way too small and its people way too savvy for you to get away with lying.
The reason people do a lot of lying is that they feel they have to say something. Or they feel they need to make something sound better. Or they don't want to get caught not knowing something, etc.
The impulse is understandable but the result makes you look foolish.
If you're in an audition, don't lie to people about your resume. If you don't know the answer to something that you realize you should know the answer to, laugh at yourself! When you try filling in the blank with SOMETHING, it becomes obvious in your behavior.
And I'm always surprised how often actors will claim something or answer something in a way that a simple visit to their Facebook page proves false.
If you don't know the answer, if you haven't accomplished certain things, if you can't be available -- be honest. If you can't be trusted, people won't want to work with you.
Now, are there times when leaving something out of the conversation is okay? Sure. I think there are things in your personal life that you don't need to volunteer. It's important to note, however, that when those things interfere with your ability to do your job as an actor you're going to have to be proactive about communicating them.
The real message is that people tend to respond to straightforwardness and honesty and see it as a strength. When I watch actors lying to cover up their supposed weaknesses, it's the lie that makes them appear insecure -- not the thing they're trying to hide.