One of the rudest things that you can do when sending your resume to prospective companies, is to not attach a cover letter to it. The cover letter is a form of self-introduction, and sending a plain resume is like a figurative slap in the face. A well worded and well thought-out cover letter can give you plus points with the HR personnel assessing your application. Be sure that your letter is straight to the point. You should sound confident and make clear your strong drive and motivation. Add here your references to prove your credibility. Most importantly, don’t forget to let the best of your personality shine through.