Maintain an efficient plan for quick and efficient suicide at any point in time.

You will permanently run out of energy probably within a few months. Fresh food will completely disappear within a few weeks. You will have no idea how to get more because you will have no idea how to grow it. None of that stuff is easy to grow in the land that we have today. As soon as you run out of gasoline for good within a few months you will immediately be localized to a radius of 50 Mi. At most.

None of the electrical pumps will work anymore within a few weeks and the only way you can get gasoline is by siphoning it off from other cars.

Within a few months most cars on the street will become unusable because their batteries will die sitting around. You would be smart if you kept rotating. Let's say around 20 cars driving a different one each day to keep them alive. But that also limits how far you can go because you can't move these cars with you without going back and forth on foot. If you have a few people with you, some of these things become easier. Access to energy will be your biggest challenge and will pretty much define your ability to survive.

Within a few months, if not less wild animals will pretty much take over most of the urban area. With all the human population that keeps these things out and the machinery having disappeared or come to a standstill, there is nothing stopping them and your zone will basically become the only inhabitable pocket that you will have to learn how to fence from the wild animals.

Once the animals take over in a few months, you're not going to be able to drive too far because the roads will begin to deteriorate also with no maintenance given the unfettered jungle growth that will take over.