Evans takes his side to the capital to contest the League One play-off final with Leyton Orient, with the chance to play Championship football next season at stake.
It was been a magnificent campaign for the Millers following promotion from League Two last year and victory over Orient would secure a first return to the second tier in 10 years.
Both clubs are taking over 20,000 fans to the national stadium for what is sure to be their grandest spectacle of the season, but Evans insists his side will treat it like any other game.
"The prize is the biggest that I have had on offer," he said.
"The chance to manage at the Championship is something I would relish and any manager that gets the opportunity to lead a team out of Wembley should be proud.
"But as much as we are looking forward to it I keep reminding my players we are not going for a day out.
"We are going to the capital, it's almost a home game for Orient and an away one for us, but we are going there to win a football match.
"The play-offs is about winning because nobody remembers the team who hasn't won, so the focus is on winning the match.
"When we got out of League Two, a lot of people thought we would be relegated, but I always retained the great belief in the squad of players and their desire to win football matches," he added.
"We need our very best performance of the season to win on Sunday if we are going to beat Leyton Orient.
"Both teams are so evenly matched, we achieved a points total that would have seen us promoted automatically in seven of the last nine years in this division so it'll be a cracker."
Source PA