1. An objective. Resume objectives never help and often hurt. Not only do they feel outdated at this point, but they're all about what you want, rather than what this stage of the hiring process is all about—what the employer wants. Your resume should be about showing your experience, skills, and accomplishments. If you want to talk about how this particular position is the perfect next step in your career, use the cover letter for that.
2. Short-term jobs. Short-term jobs raise red flags for hiring managers, who will wonder if you were fired, couldn't do the work, or had trouble getting along with co-workers. Plus, a few months on a job won't typically be useful in showing any real accomplishments or advancement anyway.
One exception to this rule is if the job was short-term because it was designed that way, like contract work or, say, working on a political campaign. Those won't raise the sorts of questions above, because you'll have an explanation that doesn't reflect on you poorly.
3. A functional format. Functional resumes (which list skills and abilities without including a chronological job history) are widely hated by employers, since they easily mask limited work experience or significant work gaps and make it difficult to understand a candidate's career progression. For most hiring managers, these resumes are an immediate red flag that you might be hiding something.
4. Your photo. Unless you're applying for a job as a model or actor, photos of yourself have no place on your resume. Since your appearance has nothing to do with your ability to do the job, including a photo comes across as naive and unprofessional.
5. A fancy design. Here's what most hiring managers think when we see a resume with unusual design or use of color: Does this candidate think that their skills and achievements won't speak for themselves? Do they not understand what employers are looking for? Do they put an inappropriate emphasis on appearances over substance? (The obvious exception to this rule is if you're applying for design jobs.)
6. Subjective descriptions. Your resume is for experience and accomplishments only. It's not the place for subjective traits, like "great leadership skills" or "creative innovator." Smart employers ignore anything subjective that applicants write about themselves because so many people's self-assessments are wildly inaccurate, so your resume should stick to objective facts.
7. Any mention of high school. If you're more than a few years past your high school graduation date, employers don't care which high school you attended or how accomplished you were there. Keep any mention of high school off your resume.
8. Extra pages. If you're in your 20s, your resume should only be one page; there's not enough experience to justify a second one. If you're older, two pages are fine, but you go over that limit at your own peril. Hiring managers may spend only 20 or 30 seconds on your application initially, so extra pages are either ignored or they dilute the impact of the others. Your resume should be for highlights, not extensive detail.
9. Your salary. Resumes don't typically include a salary history, so candidates who include it come across as naive. And by sharing that information unbidden, you'll also compromise your negotiating power later.
10. Any mention of references, including the statement: "references are available upon request." You don't need to say that you'll provide references if asked, because that goes without saying. You're not causing any harm by including that now somewhat-dated statement, but it takes up space you could use for something else.
Alison Green writes the popular Ask a Manager blog, where she dispenses advice on career, job search, and management issues. She's also the co-author of Managing to Change the World: The Nonprofit Manager's Guide to Getting Results, and former chief of staff of a successful nonprofit organization, where she oversaw day-to-day staff management, hiring, firing, and employee development.