And for goodness sake, spell check it. Then have a few people you know spell check it.
I used to do the hiring for a company. When we had a job opening, we would run a simple classified ad in the newspaper. I would get dozens and dozens of resumes.
Just to make the task easier to manage, I would immediately trash poorly written resumes. Also, unemployed people would be sent to the bottom of the pile. So, if you have a job, keep it until you find a new one. If you are unemployed, a potential new boss has to wonder why you aren't working. Were you fired? Did you have a tantrum and quit? Not the kind of things you want a potential employer thinking about.
Also, be sure to show any advancements or promotions at your current job. That will show that your current employer liked and trusted you.