Each resume you submit should be accompanied by a cover letter. Here is a cover letter template that can get you started. Remember to customize your cover letter for each new position!
[Your street address]
[Your city, state and zip]
[Your email address]
[Company street address]
[Company city, state and zip]
I am writing in regards to the [name of] position with [company name]. I believe my skill set and experience will lend well to helping [company name] achieve its strategic goals and objectives through this role.
[The middle paragraph should speak to your previous career history, skill set, certifications, etc. Remember not to repeat everything on your resume, but rather interpret and explain how you can add value to the organization.]
Thank you for considering me for this position. I look forward to hearing from you.