Limit your resume to one page. Obviously, this is difficult to accomplish with a functional resume, but it can be done. Sample different fonts. Print your resume on high-quality bond paper. If you mail your resume to a company, include a cover letter printed on the same paper.
Many companies now store resumes on a scanner.
Check your spelling and grammar. Get someone who is not afraid of honesty to critique your resume. Make use of your computer's spelling and grammar check functions. Check for consistency. For example, if you use boldface for one section heading, use it for all section headings.