Coming to Phuket soon with 7mo old baby – suggestions on dealing with the heat

I’ll be leaving in less than two weeks and, while I knew it would be hot, i just got a spike of anxiety about keeping baby safe in the heat. We live in the American south so no stranger to heat, but my babe was born in September so he hasn’t yet experienced the worst of it. I’m wondering if anyone has suggestions for helping him stay cool without just staying holed up in the hotel all day. Thanks in advance!

For context, this isn’t just a poorly planned vacation – my husband has been working in Thailand since January and this was the best time for us to visit for a variety of reasons, so suggestions to reschedule the trip are not helpful.