Apologies for however much of this is repeat from what others shared; I've been reading the thread off & on in bits and pieces. 8 Trips but last there around 2014 so things may've changed.
1.) Restaurant service is more European style, from what I understand. They don't automatically bring the check when you appear to be finishing up. To an American sensibility, this can appear gallingly slow. Just expect to signal your waitperson and ask politely for the check. I'm not the 'chat and take 2-hours to eat a meal' sort. You learn to work around it.
2.) Don't expect free refills on soda, and if you order a soda with a meal, it may come out so far in advance of the food your ice will melt, watering it down, or you'll drink it before the food comes. Order water with restaurant meals. Hit Zhung Kong or whatever supermarket you prefer and load up on soda (lots of cans of Coke Zero for me) and get your soda fix back at the room.
3.) Take a moment to familiarize yourself with the sea wasp jelly fish issue - don't repeat my pain.
Here's the thread.
4.) I concur with advice to wear a medium or thicker soled boot. Very rough iron shore in some places (look'n at you, Oil Slick Leap!) can, when you're in gear, weights, etc..., do a number of a foot. I got away with thin-soled 'booties' till I didn't, and had foot pain issues for several weeks.
5.) I think Kharon covered, this, but put your fins on and take then off in waist deep water; don't put fins on on land and try to 'duck walk' out into the water. There's rocky outcropping here and there, and it's an invitation to fall. In the shallows, choppy surge obscures visibility; you'll often find foot holds by feel.
6.) Be aware tropical sun that close to the equator can roast a person fast, even when you might think you can get away with it. Sunscreen is your friend. But some in an aerosol bottle I used on my forehead ran into my eyes and one eye's color perception was way off for awhile, so be careful.
7.) A dry bag/pack/whatever for truck keys, driver's license and a couple of $20 bills is a good idea. From what I understand some keys have circuitry or something and aren't meant to be in salt water?
8.) Some one mentioned trucks are manual transmission unless you request otherwise. Request way in advance and expect to pay a substantial uncharge.
9.) Did someone already discuss that you need CDW insurance, and the coverage that comes with credit cards may not cover off-road type vehicles/trucks, etc..., so don't count on it unless you are rock solid sure you're covered. Someone went uninsured, got in a wreck on Bonaire, and posted on the forum mentioning the cop who did the report fist bumped & obviously knew the other driver (a local).
10.) Keep your receipt from the marine park pass, since at least when I went it could get you into Washington-Slagbaai park without paying the entrance fee, and there is some nice topside scenery worth photographing. Not sure if anyone else mentioned this.
My info.'s dated but maybe will help.
Richard.