Including too much information can make employers think you aren't able to write clearly and concisely, which has become increasingly important in today's high-tech world. Your resume might not be read if it's too long, either. For an effective resume, focus on white space, bullet points, and quantifying your work experience.

Typos, misspelled words, and bad grammar mistakes can make a hiring manager think you're careless or won't pay attention to details on the job.  Show you are serious about the job opportunity and capable of doing the job by choosing words carefully and catching any mistakes.

This can make the employer think you haven't updated your resume for the job opening—or worse, that you aren't being honest.  Lying on your resume is never a good idea. Instead, learn how to properly demonstrate your value as a business-of-one.

A busy, cluttered resume may make employers think you are unorganized and scatterbrained, and that those characteristics could carry over to the job.  Make sure your resume formatting is consistent throughout the document and use headings and bullet points to organize 

information on your resume.

This will very likely make hiring managers skip your resume altogether. It's unprofessional.  Create an email account with some variation of your name for job-seeking purposes.

This shows you don't care enough about the job opportunity to send a tailored/customized resume. It might also tell employers you aren't great at adapting.  Always customize your resume for each position you apply to. That way, the potential employer will see the exact skills and experience you have

that are relevant to the position and realize you're a great, qualified candidate who could help them reach their goals.