One of the most painful parts of the job application process for so many people is writing an effective cover letter that will grab the employer's attention and compel them to ask the job candidate for an interview. Writing an effective cover letter does not have to be painful, however, as long as you are willing to turn a careful eye to your writing as well as to the job description. You will want to tailor your cover letter to the specific job for which you are applying; avoid stock cover letters that are sent out to many employers if possible.
Read the job description carefully and highlight key words. Take note of the key qualities and qualifications the employer is looking for in a job candidate, and focus on those aspects in your cover letter. Highlight your most relevant experience and skills in the cover letter and tailor those skills to meet the employer's requirements. Do not be afraid to use the exact keywords from the job description in your letter; for example, if the employer is looking for a "self-starter," be sure to tell the employer how you learned to be a self-starter by taking on an important presentation by yourself and building a team around you to effectively pull off that presentation.
Be firm in your language when writing a cover letter. Employers are looking for confidence, skill, and the ability to advocate for oneself, so instead of using phrases like, "I think I will be a good candidate," say something stronger like, "I will be a strong addition to your team." Instead of saying, "I believe my education has prepared me for the job," say instead, "The combination of my education and job experience makes me a great fit at your company." The goal is to showcase your talents and tell the employer how you will help the business succeed.
Remember that a cover letter will give the employer plenty of topics to discuss during an interview, which essentially gives you the opportunity to control the interview, at least to a small degree. What you write in your cover letter is likely to be discussed during the interview, so highlight issues in the letter that will allow you to show off your skills and talents and reinforce the notion that you are the best candidate for the job during the interview.