I can’t stress enough how important it is to tailor your resume to each specific position. It must immediately capture the attention of the hiring manager as he/she will only give it a 15-20 second glance to decide whether to reject it or to continue reading. Your cover letter should be well written, short and to the point, directly addressing your relevant qualifications in a way that will compel the hiring manager to take a look at your resume. However, it’s not enough to customize your cover letter, because the vast majority of them are never read, even often when one is expressly requested. With only a short amount of time to sift through hundreds of applications, most hiring managers and even HR will go straight to the resume, and it must be able to stand alone.
In the initial 15-20 second scan of your resume, the reader will most likely focus on the top 1/3 of the first page. Anything they need to know about you regarding your fit for their job should somehow be expressed in this space. That is why I recommend using a summary of qualifications section at the top to outline these key points in bullet form. I also advise that for each of your jobs, you include only relevant experience so as not to cloud the picture and make it difficult for the reader to see pertinent achievements. A resume is a marketing brochure, not a historical document.
I believe in using what I call the People Magazine philosophy of resume writing, as compared to The New Yorker or Vanity Fair whose articles go on and on for days. In People as in the USA Today newspaper, for each article there is a headline, a sub-headline, and a few sentences. It is easy to grasp the key points without making a huge commitment of time. Keep in mind that the purpose of a resume is not to get you a job; it is to convince the hiring manager to invite you to interview.
Regarding LinkedIn, it is true that while you may have several versions of your resume, you only have one LinkedIn profile. My rule in this case is to ensure that your LinkedIn profile is not inconsistent with any of your resumes. That will most likely mean that it will contain fewer details about your experience. This may not be ideal, but it’s much better than causing confusion with mismatched bios.
Carefully proofread all your documents – resumes, cover letter, thank you notes, and emails. Nothing is worse than saying you have excellent communication skills when you have grammatical or spelling errors.