When you next wake up, you find society has broken down (no specific reason: could be invasion, aliens, zombies), what do you do differently to any other day?
Survival mode. secure shelter, food, water, guns ammo and gather intel. Plan your next move where to go. Vehicle, gas, avoid large cites, groups. Forage for supplies along the way. Help people, Find some people that can shoot, military, police, Retired,medical, teach them how to defend themselves, using various weapons,
Ok all good so far. Hopefully Ms Pearl you'll take some other actions too since god rarely intervenes in a physical way these days. The answers to this question differ vastly depending on gun control in the country you are in. Would you try and fortify your home, or try and find somewhere more secure locally?