As this will be an ongoing series I'll keep this introduction brief..
Your overarching goal must be to achieve invisibility. Be the grey man/woman. As Chairman Mao said:
"The guerrilla must move amongst the people as a fish swims in the sea"
One of the easiest things to do, if you are a citizen, is join the party. You don't have to be ostentatious about it, just join. And as we learned studying the Nazis, an earlier number was better than a later one.
As noted in the introduction to "“A Communist Doesn’t Whine — He Shows His Teeth” Communists In Weimar Germany":
One of the rules of politics is "if your country goes communist you want to be as far up the apparatchik totem pole as you can get."
Preferably a commissar or above, putting you and yours closer to the commissary.
In a socialist paradise all pigs are equal but Hugo Chavez's daughter is a billionaire.
(actually $4.2 billion)
As to where you might find opportunity, if your country goes full Weimar with the money printing, pull your beach chair up to a spot beside the fire hose and let the splashes of the sweet, sweet trillions refresh you.
Also smuggling is always a good choice, command-and-control economies tend to create huge distortions in supply/demand dynamics.
Much more to come including case studies from the former East Bloc and the pros and cons of joining the nomenklatura.