Going to Costco, then local gun shop, get a Hummer. Make the hummer as tough as possible so zombies won't get you if flipped over. Hydrolics to flip you back over in case you do. and go to the mountains and set a Caged perimeter. Yup.
I would say stay together with a fairly large group of people. Try to hit up supper markets for food, and gun stores to gain ammunition once possible to "beat" other people to it. Stay moving, and keep aiming for the head. I would stay away from close range weapons other than a couple large knives and a shotgun and stick more to range. Stay as quiet as possible for as long as possible. Sleep on a rooftop with access only by ladder, zombies have not shown any sign of climbing quickly in most movies so its what I expect. But I don't know for sure, I guess I would find out when it happened.
Well I live out in the county in the Midwest so what I would do is get our school bus and our guns (my moms a bus driver for the school) and go to the school(we have generators there and the soccer field is fenced off so it could become a garden for food) next I would try and find some other survivors. We would the armor up the bus with parts from the other busses and go to the army reserve base and try to contact the govt. if we can't do that then we will take what supplies,weapons,ammo,and vehicles they have and dig in at the school we would also have to find an electrician or something and some wind turbines and solar panels for power also our school is surrounded by farmland so we could raise cows chickens and pigs to eat as well(this is assuming these are like walking dead zombies not like the kind from wwz where they run superfast and stuff)
What most people don't realize is that even though there's 6.8 billion people on the planet it doesn't take long for a body to decompose so while I have plenty of guns I'd just set up a tent with my wife in the middle of the field and shoot any zombies I see and wait for them to decompose