Are the public buses safe and usable for tourists or should I stick to trains and drivers

Buses are safe, incredibly cheap, and cover about 80 percent of the island, so they are great for budget travel. Two types: the slower government SLTB (usually red) and faster, slightly pricier private buses (often with loud music and aggressive driving). You pay the conductor onboard in cash, just tell him your destination and he sorts the fare and change. Keep your backpack on your lap or between your feet, hold valuables close, and use Google Maps to know when your stop is coming since announcements are rare. For long hauls the train or a driver is comfier, but for short hops buses are unbeatable value.