Here are some of the best cover letter examples out there, one of which was submitted to us here at HubSpot. Effective cover letters need to have a proper layout and sound professional to be able to do their job well and knowing how to write an effective cover letter in the correct way will be vital to your success. Here you'll also find a few effective cover letter samples that you can use when writing. Two worst cover letter mistakes you can make in the final paragraph are: Coming off needy - focusing on how much you want the job, not on what you have to offer. Cover letters are your first impression with an employer, so make it a good one. Repeating the cliched phrase “Thank you for your consideration and your time.” There are some easy tricks you can use to write an effective cover letter closing paragraph. To illustrate, here’s the best cover letter I ever received: Dear David: I am writing in response to the opening for xxxx, which I believe may report to you.