At the end of the interview, you can ask employers when you can expect to hear back from them. You may follow up with them about your candidacy after this time has passed in a respectful and polite manner.
Remember to send a thank you note to your interviewers after the interview. This plays a major role in reminding them of your interview and fit for the job. This is another opportunity for you to express your interest in the position. You could also refer back to anything you learnt new during the interview that makes you a better fit for the role. It provides another opportunity for you to clarify information about yourself. Make sure to send a note to everyone who interviewed you. If possible, add a personal touch or personal sentence that shows that you paid attention to things they said to you during the interview about their work. An email sometimes could show lesser effort, so following up with a hand written note can be beneficial. In some cases however, decisions are made very quickly and an email may be the best avenue.