What's to do there? From another tourist's point of view, Hawaii is all about slowing down, kicking back and enjoying the vibes. I would spend as much time as possible on the beaches and eating as much fresh seafood as I can
Don't spend too much time in Waikiki - see the whole island - beaches, mountains, countryside and all. Learn as much as you can about Hawaiian culture too and respect the local way of life.
As far as recommendations, must dos are Kailua Beach and Waiola Shave Ice. Other must dos for first timers: Luaus are really touristy but worth doing at least once, Hanauma Bay is also really fun if you're a beginner snorkeler, Pali lookout is breathtaking, Iolani Palace is great for history. Check out Yelp.com for more local insights.
I'm going back for Xmas (Maui, Kauai, and Big Island this time) and I can't wait
