Roy Hodgson's men are back in Group E action and will be confident of building on their 2-0 win over Switzerland in Basle last time out against the lowest ranked team in the world.
Following a dismal World Cup showing, which saw England exit at the group stage with just one point from their three games, Hodgson's side bounced back with a friendly win over Norway and their impressive victory against the Swiss.
Danny Welbeck's brace at St Jakob-Park handed England the early initiative in Group E, and another six points is expected in this international break as they travel to Estonia after hosting minnows San Marino.
But while Milner is well aware of what will be required from England in front of an expectant home crowd on Thursday, the Manchester City midfielder feels his team-mates must approach the game with their usual professionalism.
"You can't let your standards drop. We should win the game but when teams come and sit back it's never easy," explained Milner, who is set to win his 50th cap.
"It's up to us to break them down but we want to keep moving and move forward.
"Last time we played [San Marino] at Wembley [a 5-0 win in October 2012] the first goal took a while to come and people started to get a bit nervous.
"We just want to keep working at what we've been working on and improve."
With England still regrouping after what was a hugely underwhelming World Cup campaign, Milner feels the lessons from Brazil are still being learnt.
"It's nice to get back into the games but you don't forget about the World Cup," he added.
"It's important you try to work forward and the first games back are never easy.
"It's time to build on our win last month and hopefully push forward to qualify for the finals."
Hodgson's preparations were disrupted somewhat by an ankle injury to John Stones, with Calum Chambers replacing him, while Fabian Delph took part in a recovery session away from the squad on Tuesday due to a knock picked up with his club Aston Villa.
San Marino goalkeeper Giacomo Muraccini and defender Davide Cesarini could make their debuts, with Mirko Palazzi and Alessandro Della Valle having also returned from a groin injury and suspension respectively.
England have won all four of their previous meetings with San Marino - scoring 26 times and conceding just once.
Unsurprisingly, Pierangelo Manzaroli's side - who have lost 59 consecutive matches - were beaten 2-0 by Lithuania in their qualification opener last month.
