Exercise regularly, eat well, get fresh air. Same things as other demographics. Plus, you don’t ‘suddenly’ become fully protected as soon as you get jabbed.
Indeed.
"As of 15 August, 514 Israelis were hospitalized with severe or critical COVID-19, a 31% increase from just 4 days earlier. Of the 514, 59% were fully vaccinated. Of the vaccinated, 87% were 60 or older. “There are so many breakthrough infections that they dominate and most of the hospitalized patients are actually vaccinated,” says Uri Shalit, a bioinformatician at the Israel Institute of Technology (Technion) who has consulted on COVID-19 for the government.
https://www.science.org/news/2021/08/grim-warning-israel-vaccination-blunts-does-not-defeat-delta
And, as @finley has previously pointed out, for the elderly, being vaccinated doesn’t appreciably add much time to one’s life, if any.