(CareerBuilder.com) -- The phrase "shoot yourself in the foot" didn't create itself. In fact, job seekers probably coined it.
Every day, thousands of people look for a job -- and almost every single one of them makes at lease one mistake (or 10) in the process. The worst part is, many if not all of these blunders are completely avoidable.
"It never ceases to amaze me when people make mistakes, then slap themselves on the forehead and say, 'I can't believe I did that.' I feel the need to pop them on the head," says JaLynn Hudnall, of Ravenwood Forest Consulting.
Here are 20 dumb job search mistakes that experts say you can avoid with a little thought:
1. Not using a professional e-mail address.
"It is wonderful that you are proud of your heritage and cultural roots. However, please don't use 'juicygapeach' as your e-mail address," Hudnall says. "There are enough free e-mail hosts out there that you can set up a plain first.last account that is professional and non-descript."
2. Jumping into the fire without your fireproof undies.
"[Don't start] your search without a plan or much thought as to where you want to go and how you plan to get there," says Julie Bauke, author of "Stop Peeing On Your Shoes- Avoiding the 7 Mistakes that Screw up your Job Search." Also, make sure you can answer these three key questions: Why are you in the job market? Tell me about yourself. What are you looking to do next?
3. Not checking yourself in the mirror before walking into an interview.
"I once interviewed someone who had a giant piece of lettuce hanging off his mustache," says Mario Schulzke, founder of CareerSparx.com. "I should have said something to him, but it was just too awkward and instead I spent 30 minutes staring at the guy's upper lip."
4. Falling into the 'black hole.'
Many job seekers misunderstand the role of the Internet in their job search, Bauke says. "It is good for research and connections," she says, but "you are not most likely to get a job that way."
5. Being forgetful.
"One mistake that I have seen a number of times over the years is people using a cover letter template and forgetting to change the company and name to who it is addressed," says Paul Peterson, MA, MBA, national talent resource manager, human resources. "Your cover letter should always be customized to the company and position to which you are applying."
6. Going to networking events -- but not really networking.
"Real networking is building mutually beneficial relationships," Bauke says. That can be hard to do in a group setting. "Make sure you are having at least three to five one-on-one meetings per week."
7. Omitting a signature block in your e-mail.
"A signature block is a perfect place to give a brief 20-word teaser and include a link to your online résumé," Hudnall says. For example, "Georgia Environmental Engineer with 7 years experience, seeking job in new locale, click here for full résumé."
8. Casting your net too widely.
"You are not a fit everywhere and you are not good at everything," Bauke reminds. "Your search will be much more effective if you focus on exactly what kind of work you want to do and where you want to do it."
9. Not paying attention.
"Job seekers aren't reading the job description carefully and following the specific directions provided by the employer, recruiter or hiring manager," says Eddy Salomon, founder of Workathomenoscams.com and Workathomecareers.com. "The job description may state 'please apply by visiting x site. Please do not send a résumé.' But many job seekers are guilty of scanning the information provided and will end up doing the opposite of what has been described and send a résumé. Employers can't help but disqualify these candidates because it shows a lack of attention to detail and the failure to follow directions."
10. Overlooking the interviewing "gimme" questions.
Prepare to answer the basics questions: What are your strengths and weaknesses? Tell me about yourself. Why should we hire you? "You know they are coming. Be prepared!" Bauke says.
11. Not joining your local Chamber of Commerce.
"Every Chamber across the United States has a monthly get together usually called something like 'Business After Hours,' and many even have young professionals associations," Hudnall says. "Not using this an as opportunity to network and meet others in your field is a missed opportunity."
12. Having grammar or spelling errors on your résumé or cover letter.
"No matter how many résumés you send out, each customized to fit one job description, you must review each one closely for grammar and spelling errors," says Rick Saia, CPRW, content writer for Pongo Résumé . "Even the tiniest error will cast a bad impression on the hiring manager, especially if you write 'attentive to detail' as a strength. It's good practice to have a trusted friend or relative read through your documents before you send them."
13. Not being mindful of social media presence.
"Job seekers need to be mindful of social profiles and pictures they may have out on the Web that may be deemed inappropriate. In some cases employers may secretly try to 'friend' you on a given social network so they can have access to your wall and photos," Salomon says. Before applying to any job, one should search for his or her own name to ensure there isn't anything out there that would be deemed inappropriate.
14. Trying to turn an informational interview into a job interview.
"This is probably the worst form of abusing your network contacts. An informational interview is to get information, not an offer," says Ron Katz, author of "Someone's Gonna Get Hired ... It Might As Well Be You!" "When people start peppering the contact to see if there are any openings or jobs available, the person with whom they are meeting feels duped, taken advantage of, and at worst, angry and resentful."
15. Not having a LinkedIn profile.
"Many employers and HR professionals use LinkedIn as their go-to resource for more information about a candidate," Schulzke says. "If you don't have a LinkedIn profile, you are missing out on a critical opportunity to showcase your skills and experience."
16. Failing to research the company.
"At least take some time to review the company's website and use some of that knowledge in your résumé and cover letter," Saia says. "When you get to the interview, you'll need to know much more, especially to show how your skills and experience match up with the demands of the job and how your skills and experience can benefit the company."
17. Not following up after applying for a job.
"Following up is critical to set you apart from other applicants. Job seekers often neglect this key step because, for example, they applied online and don't have a name to follow up with," says Amy Olmscheid, manager of the Career Center at Capella University. "But if you don't have a name of a person to follow up with, find one. Use the Internet or use your network. Get the name of a contact in human resources or a manager in the department you want to work in and then follow up with a call or e-mail."
18. Neglecting to follow up after an interview.
"Always send a thank you note to the interviewer," Olmscheid says. "Sending your note by e-mail is perfectly acceptable, but a handwritten note is a nice extra touch."
19. Failing to ask questions at the interview.
"Remember that you want to find out about the company and hiring manager as much as you want to tell them about you," Saia says. "By passing on the opportunity to ask questions, you're sending a message that you're not that interested in the job. And employers want candidates who are interested."
20. Relying on a single job-hunt strategy.
"Some job seekers will declare that they are only using online job boards and those individuals may miss excellent opportunities," Olmscheid says. "Job seekers typically identify more jobs and make more connections that can lead to jobs when they use a multi-pronged approach. Amp up your job search with job boards, face-to-face meetings, networking at professional development meetings, phone networking and other search strategies."
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