My family came here in 1978 - Linda and I in our late 30s and our son aged 2 1/2. L and I had lived as expats in other countries before then (England, Canada, Bahamas and New Hebrides in the South Pacific), and were well prepared for life here.
It would be difficult for me to narrow my recommendations down to five tips, but I will be glad to answer any specific questions. I usually direct enquirers to an online magazine called "Cayman New Resident" for matters relating to the current cost of living, and to my own personal blog-website for comments on local politics and government policies. Anybody thinking of coming here to work should learn something about the anti-expat sentiment prevalent among our local politicians before leaving home; as a victim of that in my time, I am something of an expert on the topic.
Ask away.