Forest are a point ahead of Wednesday having featured among the pace-setters in the early stages of the season.
And Monk believes the Owls must draw on their performance in the opening stages of their 1-1 draw at Derby County in midweek to overcome Sabri Lamouchi’s side.
“We will have to play as we did in that first 35 minutes,” he said.
“That is the level we have to play at and try and sustain that as well.
“We want to go there and try and win the game, but they are a quality side.
“We are going to have to do what we did in the first 35 and try and sustain it for the 90 minutes.
"You want to play the perfect game every single time, but it is very tough in this period.
“But what you have to do is keep collecting points, ideally it is three points.
“We weren't far off at Derby.
“But it is another point and you have to keep accumulating points.
“That's the key.”
Asked about the condition of his squad after he was forced to replace top-scorer Steven Fletcher during the Pride Park clash, he said: “I am going to have to think about these three game weeks.
“You are asking a lot of the players to physically and mentally push them.
“I expect whoever goes out on the pitch to do that.”