The hot topic these days is the bugout bag. You know, a bag of important stuff you think you will need when the excrement hits the oscillating blades. What do you need really depends on what you expect. I have one kit made just in case I have an active shooter situation in my jurisdiction. It is a Level III plate carrier with extra soft armor, four magazines for the AR-15, a Tops Pry Knife to help open doors and a trauma kit on the back. I can put the plate carrier right over my uniform, thus giving me added ballistic protection and the tools I need to stop the threat and render aid.
I also have various other kits in various locations that will provide me things like extra ammo for my duty sidearm, a multi-tool, first-aid gear, flex cuffs. There is another kit in which I keep a spare sidearm, ammo, a trauma pack (are you noticing a trend on the trauma kit theme here?) flashlight, knife, multi-tool and more. And I have one of the Mossberg JIC shotguns in a tube, loaded up with extra ammo, first-aid gear, a knife or three, a water filter and sheet of heavy plastic for a basic tent. I think I'm ready.
For me, the bug-out kit requires some sort of firearm or spare ammo. When things are very bad, people might want to fight. They might want to take what is yours. The only thing that stops a bad guy with a gun is a good guy with a gun. So… Rule #1: Have a gun. Be trained in its use. Be familiar with its operation. Know its capabilities and, perhaps most importantly, be mentally ready to use it.
Rule #2: Have a trauma kit. An exchange of gunfire usually means someone is going to need medical help. If that someone is someone you want to save you will likely need, at the bare minimum a tourniquet, a compress dressing, first aid tape or wrap, bandage material or surgical sponges and gloves.