Writing an effective cover letter is incredibly important. Anything worth doing is worth doing right, and that especially applies to trying to get a job. The job market is so incredibly tight right now (and no dirty jokes, guys!), you literally cannot afford to do a sub par job. You have to simply assume that every other applicant, whether there are ten or one hundred, applying for the job you want is more qualified than you. That may not be true, of course, but by thinking so, then you have more incentive to write the best cover letter you possibly can.
Now then, what does the most effective cover letter contain? Honestly, more than anything, that depends on the job for which you are applying. The best cover letter is going to be specially tailored to whatever position you are trying for, although some of the information will naturally be the same for any cover letter.
Succinctly, a cover letter in general is pretty much an expansion on the objectives portion of your resume. Specifically, you are telling your potential employer exactly why you are the best, and indeed, the only, candidate for that job. This is incredibly important because, like say, it is crucial that you work on the assumption that you have tons of abundantly qualified people competing for this job. It is not at all out of line to say that it is completely possible for you to be passed up for a job even if you are the best candidate. Another applicant might be less qualified, but if they present themselves in a better light with their own cover letter, then the hiring manager in charge of reading them is more than likely going to think that the less qualified person wants it more, even if that is not the case. You definitely do not want that, especially if you are absolutely certain that you are the best possible candidate for the job.
The best piece of cover letter advice you will ever receive that does not apply to content involves the length. As you well know, everything in this area is strict: resumes should not be longer than two pages, your CV can be over than two pages but should not be much longer than three or four. An effective cover letter should be able to say why you are the best person for the job in one page – or less.
An effective cover letter depends on what you put into it. It is definitely difficult to write a little but say a lot. If you can manage that and further manage to show the hiring manager that no other candidate will be even half as good as you, then you significantly raise your chances of getting the job of your dreams. With a fantastic resume and a great CV, you will be almost guaranteed to get the position you have always wanted. If you still are not sure how to properly sell your job skills, then don’t forget – there are plenty of resources for cover letter help available on the Internet.