After your interview is finished, you still have work to do to increase your chances of landing the job. It's always wise to send a follow-up letter after the initial interview, thanking the interviewer for his time and adding another skill or talent that would make you suitable for the job. You'll need the interviewer's contact information to send the letter, so you'll have to ask him for his business card.
Shake the interviewer's hand and thank him for his time.
Tell the interviewer that you'd like to get in touch with him in a few days, and ask him for his business card.
Write down the interviewer's information. Some interviewers don't carry their business cards while on the job, so your interviewer may not have a card to give you. Still ask for his information, such as his name, title, address and email address and write the information on a pad of paper.
If you tend to forget things, you may want to ask for the business card at the start of the interview. After you shake the interviewer's hand and exchange greetings, go ahead and ask him for the card.