JRST,
Having at one time or another filled all of the roles in your question (applicant, initial interviewer, and candidate selection board member,) here is my advice, in the form of an oversimplified, heartwarming analogy. Note: This is based on my own experience as a recruiting O and board mbr. These are not universal standards adhered to letter-b-letter at every PRes unit across the country. Your mileage may vary.
The initial interview is like a first date with the unit. We are checking to see if we get a warm, fuzzy feeling about you, and making sure you know more or less what you are getting yourself into. Either be yourself, or act like someone you are prepared to pretend to be henceforth in perpetuity. (I recommend the former.) This will likely be fairly informal - but that does not mean you should show up with your bum hanging out of your jeans or overlook basic hygiene. Impress us. Make us want to see more.
The "test and such" are like the next 10 dates or so. We want to see if you have the basic building blocks required to satisfy the standards that we have set before we commit to a long term relationship. We are mostly into guys who are pretty fit, pretty smart, pretty available, quick thinkers, mentally agile, loyal, courageous, trustworthy, and honest. It doesnt hurt if you have a dash of experience in your field or as a leader in general. (I know, we are hard to please and high maintenance.)
The board interview?
That's the date where we take you home to meet our father. This is where things get real, and if this doesn't go well, he won't let us see you anymore. This will be formal. There will most likely be a script, and your answers will likely be scored. You may not be the only applicant who gets this far, and your scores had better stack up against the other suitors. To do well in the interviews I have been part of, you would need to demonstrate that you have done some homework on the unit's role and your trade; know a bit about current affairs (relevant to the military
have considered the impact of your new career on your regular school/work/family life and have considered how to mitigate that impact; and be able to answer some simple, relevant questions about yourself and your experience (IE "Tell me about a time when you resolved a conflict." "Tell me about a time when you had to overcome adversity.")
To sum up:
Initial interview = first date. Don't Suck.
Tests etc = Demonstrate your potential. Work hard and pass.
Board interview = meeting Dadddy.
A final thought - Do you know what the recruiters main role is? It's to recruit people - not to scare them off. If you get to that board interview, it's because we have an opening, and we want you in it. Be articulate, be honest, and be aware that "I don't know" is a terrible answer, second only to a lie as the worst thing you can say in an interview.
