Make sure that you always have actions words in your resume such as: Spearheaded, Collaborated, Championed, Awarded, Facilitated..... rather than just writing words that are most common such as Participates, Handled, Provided.
This is a great site that shows thousands of Action Words that you can apply to your resume.
Avoid long sentences, shorten them with bullets.
Do not list references on a resume - most employers know that they are going to ask for these and that you will supply them once they get to that point in the hiring process.
Always have a title under your name header that uses the words that are described in the job description and PLEASE ensure that it matches your experience. An example would be to center the words: "Sales & Executive Business Operations Professional" or "IT Sales Management". This will ensure immediately, the first thing they see is what you can do!
Never put hobbies on your resume or personal information! Also, unless you are directly out of school without alot of experience, it is not necessary to include your GPA or sororities...etc....