I don't know how to access bonefish flats on Grand Bahama without a guide, and his boat, specifically. My wife and I fished with Bonefish Sam, Sam Taylor. You can DIY from the beaches you can get to. And fish some clousers in the marina areas - watch out your back casts for people on the docks. There are all kinds of fish lurking around in the marina areas. We had severe wind and only got to fish with Sam one day. Some guys stayed at an Orvis lodge on the east end of the island and said they got out to fish every day, but it was pretty windy there too. On the north side where we were, Sam wouldn't even launch his boat. It would have been risky, so he said save our money for a calmer day. I did catch an 8# bone and two smaller ones the day we did get out however.