Brayden, When tailoring your resume towards a specific job application, I would focus on the main responsibilities of the new job you are looking to land. The employer will want to see that you are capable of performing tasks similar to those that you will be required to perform at the new job.

I would say that it depends on the employer’s instructions on the job posting, for example: If the posting instructions request both resume and cover letter - then use separate PDF or DOC attachments. It looks cleaner and makes it easier for employers to share, read, and review. If the posting request is for resume only - then attach the resume to the email and use the email body to write a (brief) intro in a cover letter fashion. Keep it very brief because most of the time it doesn’t even get read.

The key is to identify words that are prominently or repeatedly used on the job description. Don’t be afraid to use similar job descriptions from other companies to increase your keyword count. You can use a word cloud generator to extract the most prominent words (http://bit.ly/1domOkD). Identify as many keywords as possible and structure them into your resume. You can test your resume by comparing it to ads for jobs you want to target but if your resume doesn't include more than 50% or more of the keywords in the job description then you more than likely will not get a call back for an interview.

Depending on what job you are applying for, for example a warehouse position you would put Inventory specialist Inventory Quality management Safety coordinator Key words ( specialist, quality, coordinator ) those three words will make your resume be detected 3 times because they are high on the spotlight list. Spread them out through your resume specialist on the top coordinator in the middle and quality at the bottom, that way your resume will be detected 3 different times each time you submit it