That's an excellent question! As a software engineer, I've endured many, many interviews. The hiring process typically requires multiple interviews. I offer my interviewing rules as an aid.
Rule #1: The objective is not to receive an offer from the first interview. The objective is to get the second interview, which is almost always required.
Rule #2: Think counter-intuitively. Think of the prospective employer's interests instead of your own. It's not about you. Don't think "Do I want to work here? Would this position be good for me?" Instead, think "Can I help the company?" Be humble. You have already decided the company/position might be good for you and you'll never know for sure until after starting a position.
Rule #3: Forget about pay, benefits & duties. Do not ask about it. None of that matters if you don't get an offer. Avoiding those questions often leads to an offer better than advertised.
Rule #4: Appreciate and like everybody. You don't know the interviewer(s). It's a real advantage if the interviewer (or any contact) feels that you like them. You can't fake it. Learn to assume every person you meet will end up being your best friend. It stands out. You can always change your mind later.
Rule #5: Avoid asking questions (*save one - see below) during the interview. Interviewees that ask questions invariably violate rule #2. When answering questions, avoid saying "I/me/my" (interpersonal/business communication skills). Remember rule #2. Interviews usually conclude with "Do you have any questions?" (see rule #11). If you must ask questions, try to save them until then. If you feel pressure to ask relevant questions, ask them with rule #2 in mind.
Rule #6: Always be honest. If you lack a skill they ask about, say "I don't have much/any experience with [that skill]" Remember rule #2. Honesty can get you an offer even if you don't seem to be qualified for the position. I once received a very good offer (after several interviews) for a position after the initial interview, when I said I didn't think I was a good fit- the job didn't seem to match my skill set (rule #2). As it turned out, they didn't really care about what they specified in the job description - they wanted a good engineer (or somebody they like). I got the job with an extra $10K over the advertised salary (rule #3).
Rule #7: No jokes.
Rule #8: No personal stories. (Rule #2.)
Rule #9: 'Mirror and match'. It's a sales technique designed to build instant rapport. It makes everybody tend to like you in minutes.
Rule #10: Follow the universal interview guidelines. Do your homework and visit their website. Dress professionally. Be well-groomed. Do not use perfume/cologne. Be polite and mind your manners. Be 10-15 minutes early!
Rule #11: At the end of the interview, when the interviewer asks "Do you have any questions?", ask this: "Why do you like working here?" Ask it verbatim. Practice asking the question so you can deliver it naturally. This one is very important! It's your *single-use* secret weapon. If you know you'll get a second interview, save it for the second interview. You can always answer "No questions. You have explained it well." It never hurts to give a subtle professional compliment to the interviewer.
Rule #12: Once the interview is concluded, thank the interviewer and express your *sincere* appreciation. "Thank you very much for your time. I greatly appreciate it." Be sincere. If you don't really appreciate it, they'll know.
Notes:
Rule #4 must be learned & practiced. Fortunately, you can practice with anybody you meet anywhere and it doesn't take long to become skilled.
Rule #9 'Mirror and match' is also a learned skill. However, having a basic understanding alone will help. I found a quick primer here: www.maxxmktg.com/mirror.html
Social media can ruin the best interview of all time. Twitter, FB, Instagram, etc. can cost you dearly. Puppies and kittens are okay - delete the rest. Also, while you are busy interviewing, someone might take a look at your vehicle. Make sure the interior looks clean and there are no bumper stickers, etc.
Much of the above applies to other areas of life.
Best of luck to you. If you take my suggestions to heart, I suspect you won't need any luck.