Congrats to all those invited for R2! I'll go out on a limb and on behalf of the R1 Admits, I am excited for you. I really enjoyed the interviewing process (met many people interview day that I am now friends with/reunited with at ASW).
Just some thoughts on interviewing--
1) Be online tomorrow right when interview scheduling opens, and be prepared. Know your schedule and which days of the week are ideal. I found the early AM slots did not go as quick, so it might be less stressful to aim for those rather than refresh and have a panic when you can't get your preferred time.
2) Think hard about trying to come to campus. I am local to Boston so on-campus was the default for me, but if it is within your means to come to campus to interview, it is worth it. I spent 2 days (day before interview, day of) wandering around, doing a class visit (HIGHLY recommended, see below), talking with other interviewees (many of whom I am now friends with), etc. HBS offers a lot of programming on campus around the interviews and I think that was very valuable. Set my mind at ease too. That said, I've met people who interviewed out of the country or ex-Boston and found that to be a positive, professional, and consistent experience to on-campus.
3) Do a class visit if you interview on campus. Seeing the case method live in action was the highlight of my interview experience. It gave me a much clearer sense of how I might fit in to the HBS community. Also found it somewhat relaxing - guests aren't in the hot seat.
If you can, schedule a class visit before your interview.
4) Throw all of your thoughts away about your GMAT, stats, etc. If you got an invite to interview, they aren't relevant anymore. Focus on your story, why HBS, and get in the mindset to say "I can see myself here."
5) Don't try to prepare. Really, Dee wrote to us that you can't prep for the interview. You really can't. I got asked questions about two obscure interests on the most blighted part of my app (the last line of my resume). Other people I know got grilled on their job. Some people got management consultant type questions. It's a complete roulette, specific to you.
6) Make as many meaningful acquaintances as you can at interviews, wherever they are. I am still talking to the people who sat next to me waiting to be interviewed - plus the reunion was that much sweeter at ASW seeing friends make it through the needle's eye. Get in the mindset that these are your future classmates - not your interview competition.
7) Try not to worry about the 30 minute time limit. I'm sure you all know that interviews are a blisteringly short 30 minutes. I was fortunate in that mine wrapped up organically in that time. But it's the interviewer's job to keep it to 30 minutes, not yours. Offer answers that are honest, direct, but evident of your personality, and the interviewers will dial things up or down as they would like.
8) Think of your second "silent" interviewer as a potential third party to the conversation. Perhaps my experience was unique, but I got some dialogue going with my first and second interviewers (who is supposed to be a seen-not-heard observer for the most part.) At the beginning of my interview, this had a huge impact in putting me at ease and making my time feel conversational. Not sure you can manufacture this, but if your second interviewer engages you, engage them as best you can.
9) Don't focus on the reflection essay until after you finish. After grabbing my interviewer's cards (write a handwritten thank-you!!!), I went and wrote down all the questions I was asked right away. But not a second before.
10) Don't be afraid to write your real feelings on your post-interview reflection. Don't fret about the length - I've heard varied responses on how much people wrote. My response was about a page and a half. I wrote mine like a letter, addressing things I enjoyed about the interview, honed in on the most interesting part of the interview, and added one topic I wish we had covered. Let your personality show. Use your natural voice and try not to be too stiff. And, from a few admits I've met, it's okay to voice some disappointment or things you wish had gone differently. I don't think there are any "catches" in the process.
11) The interview process is the most personal, private part. I was more private with my application process than some - I didn't solicit any outside opinions during the written app. But thinking about interviewing, I really focused on looking inward on myself, where I've come, and where I'm going. I'm sure there are many paths to success, but I think in my case the interview and post-reflection process were done in isolation without outside influence.
If anyone has any other thoughts or questions, would be happy to be a resource. And congrats again!
Wow. This is great. Kind of wish I'd seen this before my interview!