I lived through The Cold War and the Soviet nuclear threat. Here are my tips:
1. Live your life! You never know when your last day is going to happen.
2. Don't worry about "surviving" an all out nuclear war. The dead will be the fortunate ones. If you build a foolproof bomb shelter, stock it right, and manage to emerge a year later, there will be nothing to emerge to.
3. If you live in a major target area, it will be over in a literal flash. When the sirens blare, grab a good stiff drink, smoke a big ol' spliff, or make love to someone you truly care for. Go out on a high note.