We knew where we were staying: My brother and his wife's condo in Mililani.
We knew what we were driving: I got a sweet deal from Discount Hawaii Car Rental on a Mustang Convertible (or similar--oh how I hoped it was not something similar). It was a surprise for my hubby who thought we were getting a compact. This website was awesome and hooked us up-as in $300-$500 cheaper than what I was finding on all the travel/car rental websites! I highly recommend it and I am not getting paid or compensated in any way to say that. :)
We generally knew we were going to do certain touristy things: I have been to Oahu a couple of times but my hub had never been. So we got tickets to the PCC, we were going to hike Diamond Head Crater, snorkel at Hanauma Bay, etc. But we were also willing to add anything to the agenda at any time. For some reason that was one of my favorite things about this trip. It was EASY.
We knew what to pack. Sunscreen, sunscreen and more sunscreen (and yet I still got sunburned...I will never learn).
We had a big stash of cash for spending. Which probably is not the smartest thing to do but we did it anyway.
The night before our trip and I was totally not excited like I thought I would be. And I realized that was because I had never left my babies before. Ever. Not even for a night. I cried myself to sleep that night worrying constantly that they would wonder where we went, or not have fun, or not sleep well, etc., etc. Then the time to leave finally came!