Job interview mistakes can ruin your chances of a job offer — even if your resume and cover letter are in tip-top shape, and you're strongly qualified for the open position.

If you don't have trouble landing an interview, but can't seem to get a job offer, maybe it's time to improve your job interview skills. Then you can show potential employers the real you and boost your chances of landing that dream job.

To be at your best in your next job interview, review the following tips on how to avoid making five common job interview mistakes.

1. Being nervous

Problem: You don’t come across as confident — or competent — because you’re so nervous.

Solution: Job interviews can make you nervous for good reason. There’s a lot at stake. Luckily, you can often keep jitters at bay simply by being prepared. Know what’s required for the position. Familiarize yourself with the potential employer, its customers and some of its challenges. And find out all you can on the Internet and through your online network. Then practice talking about yourself and your qualifications.

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2. Getting distracted in phone interviews

Problem: You’re uneasy with phone interviews, because you can’t see the interviewer — and get a sense of how you're doing.

Solution: Since the interviewer can’t see you either, what he or she hears will shape how you're perceived. So speak clearly. And remove all noisy distractions such as barking dogs, the sound of kids playing, ringing cell phones and door bells. To help you focus, jot down important points as the interviewer talks. And have some questions of your own ready to ask. Smiling when you respond will help you come across as more energetic and positive — even if you can't be seen.

3. Being unprepared

Problem: You get caught off guard by unanticipated questions.

Solution: Do your homework on some of the most common interview questions and practice answering them. Here are a few to start:

  • Can you tell me a little about yourself? Your answer should be brief. But quickly show the hiring manager how your relevant skills and experience could benefit the company.
  • Why do you want to work for our company? Your response should make clear that you’ve researched the organization and know why the job is a good match for your skills. It can be helpful to mention specific projects or programs that have impressed you.
  • What are your strengths and weaknesses? The first part of this job interview question is usually easier to answer. When describing weaknesses, make sure to name a specific weakness(not just “I’m a perfectionist!” or “I’m too committed to my work”). Then describe the steps you're taking to overcome it.
  • Where do you see yourself in five years? Talk briefly about your goals for professional growth and career advancement. And explain how and why you see a future with that organization.
  • Do you have any questions for me? Have specific questions about the company and the available position ready. Or ask the interviewer what he or she likes most and least about working for the company.

4. Being overly confident

Problem: You don’t know the line between being confident and arrogant.

Solution: You need to express confidence in yourself and enthusiasm for the position​. But do it chiefly by speaking honestly about your qualifications and letting your experience speak for itself. If you answer every question with bravado, you may come across as insincere.

5. Being negative

Problem: You make a number of negative comments during interviews.

Solution: This interview mistake can be highly damaging to your chance of getting a job offer. Even if you’ve just had a bad layoff experience, don’t speak critically about your former employers, colleagues or companies. It will simply make you appear petty. Also stay away from self-deprecating comments: They don’t help you show a positive image or demonstrate your competence or confidence.

This post has been updated to reflect more current information.