Holiday to the Caribbean with 5 month old - what will i need?

Hi

i have just found out I am pregnant with my first child and already have a holiday booked to go to the Caribbean in may 2019. The baby will be roughly 5 months old, I just need a bit of advice on precautions, things I will need, suggestions or anything else that could help me get a better idea of what to do. 

Thanks in advance