Job interviews can be stressful at the best of times. That's understandable - especially if it's for a job you really want. The reality is, far too many people fail their interview before they really get started - because they don't prepare properly and they don't present the best image of themselves.

We're going to look at some of the reasons many people mess up their interview. If you get these ironed out, there won't be too much left to be stressed about - you'll be able to focus on being a great prospective employee and wowing people into giving you a job.

1. Incorrect dress

Appearance matters. Whilst interviewers shouldn't be concerned about how good-looking you are - they will make huge judgements based on how you're dressed. Aside from going in top hat and tails, you can't really be over-dressed for an interview. Even if it's for a casual or unskilled role - staying smart is important. It'll make more of an impression about your professionality than someone who turns up in a t-shirt.

You'd be surprised how many people turn up for professional job interviews in smart-casual clothing. If it's in an office, you should wear a suit and tie. Jeans are a no-no. If you don't have a suit yet, that's understandable. But you should still wear a shirt and tie with smart shoes.

2. Poor research

Interviewers like to see that you've learnt something about the company. They want to know you can do your own research and have grasped the basics of what they do. Being under-prepared is a big turn-off. They like it if you ask relevant questions to the role and aren't just acting like you've been forced to come to the interview. Interact with them - and show some personality.

3. Smoking

Whilst interviewers shouldn't ask you if you're a smoker - being one could be a problem. No interviewer will admit to this being the reason they rejected you for the job - but smoking is becoming more and more frowned upon in acceptable society.

If you smoke - your hair and clothes will probably smell without you even noticing. If interviewers can smell smoke on you (especially on your breath) it'll say a lot about how you present yourself as a whole. If you can get it right in an interview, they'll have doubts about how you're going to smell when interacting with customers.

More and more people are choosing to buy e cigs. They're a great way to ease yourself off of proper tobacco smoking and they don't make you smell in the process. You'll still be able to get a small fix of nicotine without ruining your health with the chemicals associated with tobacco. Although you shouldn't get your e-cigarette out during your interview - your employer should look favorably on someone who is doing their best to quit.

4. Being too focused on money

Most people work for money, that's understandable - but you don't want to act like a mercenary in your interview. There'll normally be a natural time to discuss wages - but this'll normally be towards the end of an interview. Don't act too obsessed with pay or ask them about it too soon.

People make tons of mistakes in job interviews. Hopefully these few tips should help you iron out those problems so you can be an interviewing success.