What's an easy way to keep myself safe from phishing attacks?

Asking this question because I often get afraid when read articles like 'nuclear power plant was hacked because some employee opened some email' and because I also think it would be devastating and hugely damaging to lose my information to a malicious actor.

I use OS X's mail client. Delete all junk mails without opening them (I regularly receive mails saying your account is hacked, but none of them have my password and hence I think they're illegitimate).