Many clients that I've worked with have been surprised by my suggestion that the cover letter is more important than the resume. However the cover letter is often the first thing read by a prospective employer or recruiter, so you need to make a bold and engaging case for yourself as the perfect person for the job, or you risk your application ending up in the 'no' pile!
So how do you write a killer cover letter?
Step number one is tailoring your professional profile to ensure 'who are you?' is answered in the first few sentences of your letter. Don't cut and paste your full profile from your resume, but extract the most relevant parts to give the employer a clear understanding of who you are.
Step number two is researching the organisation and job. Your cover letter needs to show enthusiasm for the role, and this can only be conveyed with a good understanding of what the job entails and how your skills and experience are the perfect match for it. This excitement and enthusiasm for the role needs to be in the first paragraph of your cover letter, along with an extract of your professional profile (step one).
Step number three is ensuring you explain how you meet the key selection criteria (KSC). If a separate response to the key selection criteria is required, this can be brief. However, if no separate KSC response is required, it's a good idea to list a brief (1-2 sentence) response to each criteria. This may seem like overkill, but it makes an employer's life a lot easier if they can clearly see how you can meet the requirements of the job. If there are no defined KSC then try to work out what they are looking for from the job advertisement.
Having a killer cover letter will make the employer or recruiter's life easier, encourage them to read your CV and then hopefully call you in for an interview!