How Should You Follow Up After An Interview?

The follow up would depend on the nature of your interview , the job and the company. Following are some follow up techniques:

Thank you note.
A thank you note should be sent immediately following an interview to each person you met. A thank you note may be handwritten but a word-processed letter reinforcing the points you made during the interview is better. Always personalized thank you notes and never send the same letter to various individuals on the interview panel.

Additional information/documentation.
If you were asked to submit your documents or a sample of your work etc. do no delay sending the information. You may attach a brief handwritten note with the document.
Follow up calls.
Calling up to determine the status of the job and your application will not make you appear desperate. It will show your employer you are interested in the job. At the end of your interview you may ask when you can expect to hear from them.

Continued networking.
If somebody referred you for the job, follow through on all leads, and give occasional status updates to the person who originally referred you.

In all your follow up activities, be sure to spell the person's name correctly and use his or her correct title.

Polite follow up is shows good business etiquette and helps setting you apart from candidates who don't follow up.

After the interview, follow ups are very important. The first thing you must do is write notes to yourself about people you met, impression you have, and what follow up is necessary. Record keeping is very important, especially if you are interviewing with many different companies.
Generally, you will also want to follow up with a thank you letter to the person or people with whom you spoke. This courtesy keeps you on the interviewer's mind and may serve as an opportunity to elaborate on some aspects of the interview. If you are practically interested in the firm, more than others you have spoken to; let them know this as well. In the reserve case, when you known you are no longer interested in the company, say so. Someone else may want the job and may be waiting for you to bow out.
After you have thanked the interviewer, you have essentially completed the sales pitch. This is often most seeking time for someone seeking employment. You need to be patient and wait for the response. People mostly say how long should they wait, you should try to find out at the interview when you are likely to hear from the company, either about an interview with other people or an actual offer. You do not have to be so courteous as to wait in agony for weeks when a simple question would clarify the time frame.
If you do not here within the allotted time, you should wait a few extra days before calling the company.

Do a follow interview letter like this one below..

Dear Mr. MilesRE: Follow Up on Job InterviewThank you for taking time off your busy schedule to interview me last Tuesday, January 15, 2011 at your office.I am grateful for the time with you and Ms. Larimore who have been so helpful and informative about the position of Product Controller, which I was applying for. The more I hear about Sprightly Canning Industry, the more intrigue I am about the position.I would like to seek some clarifications about the Product Controller position too, as I did not think about them during the interview.1)   Would the Product Controller be involved in assessing the quality of incoming materials before running through the internal production system?2)     How many types of report is the Product Controller required to submit?I am computer literate so it would not be a problem for me to generate reports quickly.I look forward to your favorable decision for me to join Sprightly Canning as soon as possible.Thank you.Yours sincerely,Marcus Sarno