Cat Island is remote and rugged, so preparation is key. Insect repellent with DEET or baby oil (a local trick for sandflies) is a top priority, especially for sunset strolls. Pack sturdy hiking shoes for the rocky trek up Mount Alvernia and water shoes for exploring the limestone-edged "blue holes" and reefs. Since the island is sparsely populated, bring a reusable water bottle and a portable power bank, as you may be far from amenities during your day trips. Cash is essential here; while some resorts take cards, many local eateries, grocery stores, and the few available taxis are cash-only. Finally, bring a lightweight rain jacket and a snorkel mask—you’ll want your own gear to explore the pristine, hidden coral heads at your own pace.