Use proper formatting Make sure to avoid excessive white space and to use the space on the page. Avoid using more than one page if possible definitely no more than two. Highlight key points with bullet lists and make sure your paragraphs are clear and concise. Resumes are not the time to be wordy. Be straight to the point.
Avoid being vague If you have references include them. Dont say available upon request. If you have gaps in employment explain them clearly. They will probably come up in the interview anyways. Being prepared in advance by giving complete information in your resume is better than being caught off guard in the interview or worse skipped over all together.
Add in a list of skills Your resume is no place for modesty. Highlight your skills especially if they are specific to the job youre applying for and list where you gained experience with that skill set. Instead of being general give concrete details and highlights. For example list your experience with Microsoft Office or even a particular piece of software over computer skills. Make sure to include plenty of competency statements.
Remember you resume will be read by humans as well as by machines which will scan for the right keywords. So put some time and energy into your keywords when you write. Resumes must grab the attention of both the human and the computer scanner.
Review the Job Posting and Description Carefully A lot of the time job-hunters will write one generic resume and send the same generic resume to every employer. This is one of the biggest mistakes facing job seekers because it produces so-so resumes that dont necessarily match the employers requirements.