Most people start their jobs with the best of intentions, never thinking they could be fired. After all, that's a fate reserved primarily for incompetents and workers caught with their hand in the company till, right? Wrong. You might not realize just how slippery the slope out the door can be.

To guard your job security, be sure to avoid the 10 common pitfalls on this checklist from Jennifer Star, a New York City-based corporate recruiter and trainer:

1. Lying on Your Job Application or Resume

Tell the truth from the start, because you will be held responsible for the information you provide -- and your employer will check it. Generally, educational background checks can take up to a month after hire. "I recently had a candidate fired from a large financial company after being there for a month, because she lied about her educational background," Star says. "This woman did not need a degree for her editorial assistant position but said that she has one anyway -- and one month later when the cat was out of the bag, she was immediately let go."

2. Being Indiscreet About Your Job Hunt

If you are in the market for a new job, don't send your resume from your office computer, which most likely is monitored by IT. Assume your instant messages (IMs) and emails are fair game as well.

3. Gossiping

You never know who is listening, and in cubeland, walls really do have ears. The safest bet? Keep gossip to yourself, and never repeat anything you hear. Winding up on the wrong side of the rumor mill can cost you more than somebody's trust; it can mean your job.

4. Taking Too Many Personal Calls

Spending much of your work time orchestrating your own personal business usually results in being given an opportunity to spend all of your time on the phone on personal business -- looking for a new job, Star warns.

5. Drinking at Work

One of the quickest ways to be shown the door is drinking too much at lunch and walking into a wall. Maintaining your own clarity is extremely important. Staying on top of the mountain of details that go into making a business run smoothly requires focus -- and sobriety.

6. Surfing the Web Excessively

Spending much of your workday cruising around cyberspace puts you just a point-and-click away from unemployment. And checking adult-oriented Web sites on the job is a definite no-no.

7. Becoming Romantically Involved with the Boss

While it may make for great water-cooler discussion, a boss/direct-report romance can easily end with someone out of a job. (Hint: It's usually not the boss.)

8. Forgetting to Double-Check Your Figures

When working with numbers, scrutinize your work carefully. One stray zero could make the difference between being employed and unemployed, advises Star.

9. Alienating Your Coworkers

To do your job effectively, you'll need the cooperation, support and good will of those around you. Becoming detached from those you work with could get you replaced with someone who can work well with others.

10. Pointing the Finger at Everyone but Yourself

Take ownership of your job. If you make a mistake, own up to it. Don't try to sweep your mistakes under the carpet -- or worse yet, blame somebody else -- because the truth will usually come back to bite you on the bottom line. And nobody wants to trust or employ a liar, says Star.