Unless you just want to sit on the beach and veg out for a week, you'll probably have some excursions and activities you want to do when you travel. I spent a lot of time recently traveling throughout Asia and here is what I have to say --> a personal tour guide is the bomb.com <--
Not only should you do research on what you want to see before your trip, but you should also book in advance! The definition of vacation is "an extended period of leisure and recreation." So why put yourself in a situation where you have to plan when you get there? I don't want to spend my time at the concierge desk, searching on google, or being on a tour bus with a crowd of people.
Call the hotel or resort ahead of time, book things over the phone with the concierge, spend that extra $ on a private guide (this will save you time and let you see exactly what you want), print up your items of must-sees and best day/weather to view.
My tip? ...
Ask the locals for their recommendations for food and activities and take advantage of what your hotel has to offer. I've also found the best area for reviews are on TripAdvisor because you'll get honest opinions from other travelers like yourself!