A resume is supposed to be a generalized single-page view of your experience.
Have
Someone to look over your resume so they can catch mistakes
Descending order of experience
A link to a more detailed Curriculum Vitae
Publications
External links which show you are productive
A brief cover letter only if the position is different from your experience or you have been out of the game for a while, explaining why you are relevant or what you have been doing to stay up to date.
Have Not
More than one page
Experience older than 10 years
References
Images
Misspellingas*
All specific versions of operating systems or hardware brands
*intentional