Some job hunting gaffes are obvious -- or at least they should be.

For instance, you don't want to talk trash about your last boss, even if the ogre is known in the industry for hurling paperweights in meetings. And unless you're interviewing to be the next Sports Illustrated cover model, you certainly don't want to show up for an interview in beach attire. That's what one failed banking industry applicant recently did, mentioning she was on her way to a weekend jaunt, according to New York City executive coach Andrea Nierenberg.

But there are some mistakes even conscientious job seekers make that can derail them. So you'll want to make sure you avoid these mistakes to maximize your odds of success.

Mistake No. 1: Fixating on Your Resume

You obviously don't want to send it out with typos and coffee stains, but obsessively editing it and formatting it for weeks will put your search behind schedule.

'Recruiters and employers skim the resume,' says Caroline Ceniza-Levine, a partner in the career coaching firm SixFigureStart in New York City. Once you've got a clean resume, dive into sending it out.

Mistake No. 2: Applying Through HR

Your resume is likely to get buried in among the other ones that applicants have submitted through 'official' channels, say experts. Discretely let colleagues know you are looking for a job, so they can introduce you to their highest-level connnections at companies where you'd like to work.

'If you have a contact for a senior person, use that contact -- no matter what,' says Albany, Calif., career coach Simma Lieberman. It's the best way to get an interview quickly. (Obviously, you want to be very careful about sharing the news that you're on the hunt among current coworkers).

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Mistake No. 3: Winging the Conversation

Know exactly what you'll say if an interviewer asks you standard questions such as what you know about the company or why you're interested in working there. Don't just trust yourself to think up an appropriate answer on the spot, when you're likely to be nervous.

'Have a few top-line comments prepared,' says Nierenberg. And make sure your points are very concise, she adds. It's more important to listen than to crow about your accomplishments.

Also find out in advance with whom you'll likely be meeting, so you can prepare adequately and research each person online. 'I know one CEO who told me a candidate came to interview with her for a senior-level position,' says Nierenberg. 'The candidate looked at her and said, 'What is your role here?' The CEO said, 'I think we're finished here.''

Mistake No. 4: Mentioning the Wrong Credentials

Today's employers want to know that you are a producer who delivers concrete results that will help with overall company goals. So, for instance, you probably won't catch their eye if you mention you have a particular skill, such as using a particular customer relationship management software. Lots of other people probably know how to use it, too.

However, you will definitely get noticed if you can truthfully say you cut costs in your department by $1 million a year or brought in an account worth $750,000. 'Differentiate yourself,' says Ceniza-Levine.

Don't be afraid to be creative in how you get your key selling points across. 'One of my clients who just got a job as a manager of a hotel chain sent an incredible slideshow of why they should hire her,' says Lieberman. Wouldn't you want to hire someone like that?

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Mistake No. 5: Failing to Put Your Phone Away

It should go without saying that you should not answer your mobile phone during an interview -- but it's worth repeating because so many people do it anyway, says Nierenberg. And when you're sitting in a lobby waiting for an interview, don't play music or watch a program on your iPhone. 'That looks really unprofessional,' Ceniza-Levine says.

Mistake No. 6: Poor Clothing Choices

Sometimes these are painfully obvious: don't come to a bank interview dressed like you're ready for a day of fun in the sun, for example. Other times, the mistake doesn't become apparent until it is too late to fix.

Wearing flip flops to an interview with the intention of changing into dress shoes in the restroom can backfire. 'When you walk in, sometimes you'll see the person you're interviewing in the lobby or going up the elevator,' she says. Then it'll be too late to change -- and you'll start off on the wrong, er, foot if everyone else in the office is wearing formal, closed-toe footwear.

If you're a woman, check out how you look in camisoles worn under a suit jacket to make sure there's no unintentional va-va-voom effect. 'You have to know what people are going to see if you lean over,' says Ceniza-Levine.

Mistake No. 7: Taking Your Foot Off the Gas

Many job seekers slow down their interviewing the moment it seems like an employer is getting interested in making an offer. But that's exactly when you should be revving up your search to get other offers, so you can compare, says Ceniza-Levine.

What happens if the hiring manager who just interviewed you wasn't all that interested after all -- or goes out of town on vacation? 'All of a sudden, you've put your search on hold for a month,' says Ceniza-Levine. Keep up the pace. You'll be glad you did.

The Investing Answer: Prepare, prepare, prepare, and be as professional as possible. Practice answering interview questions. Research what a prospective employer does and who the power players are. Use your connections to see if you know anyone at the company.

Above all, don't be happy with just getting the interview. Keep working and preparing until you've closed the deal. That will make all that time that you've invested in preparation absolutely worth it.