The Latics will join the likes of Sunderland, Southampton and Wimbledon in the Wembley history books if they overcome City and Martinez is aware of the impact such a win will have on the game.
"You have to dream and the bigger the dream the bigger the achievement. Winning the FA Cup would be there forever," said the Spaniard.
"Just arriving in the final is a photographic moment in the history of our football club. Winning a major trophy would take our club to a different level.
"We are all well aware what this could mean. There are a billion people watching this game. It is one of those key moments that help develop awareness.
"When we signed Roger Espinoza he was already a Wigan fan, which makes you aware of our exposure around the world is bigger than many people think.
"But Saturday is as good as it gets and we need to take advantage.
"When I came here in 1995 there were around 1,500 people watching us in what is now League Two.
"Saturday we will be taking 21,000 to Wembley, which is incredible.
"It is a great example of how football can develop in a town and what you can achieve with it. It is difficult to describe."