You may use the same block format for your name, address and phone number that you used on your cover letter and resume.
City, State Zip
Dear Mr./Ms. Recruiter’s Name:
This paragraph should open by thanking the employer for his/her time. However, do not apologize for taking that time. Mention the date of the interview along with something he/she might have said during the interview that made you more excited or interested in the position.
The second paragraph should refer to something about your strengths or qualifications that were discussed in the interview. Also mention any additional skills, strengths, or experiences that you want to emphasize to strengthen your candidacy. If there are any issues that need further clarification, this is the place to do it.
Close the letter by restating your interest in the position and the company. State your excitement upon hearing from him/her and offer to provide any additional information. You may wish to include your phone number and general times that you are available.