The 20-year-old booked his place on the plane to Brazil 2014 with some scintillating displays in the Premier League but his Toffees colleague Naismith believes the hype could distract him from the task in hand.
The Scot said: "Playing for Everton much more this season has definitely made a big difference for him. He's a player with an unbelievable amount of talent and rightly deserves to be at the World Cup.
"There's a lot of pressure that gets put on him. Without doubt, he's got the talent but I don't think there should be as much pressure put on him.
"Just let him go and play. I'm sure the manager will play him when he sees fit and when it's right but he's a massive player now and he's only going to get better."
With England manager Roy Hodgson expected to name a back five of Joe Hart, Glen Johnson, Gary Cahill, Phil Jagielka and Leighton Baines, the identity of his midfield remains a mystery.
Only captain Steven Gerrard appears to be guaranteed of a starting role, with the likes of Raheem Sterling, Jack Wilshere, Adam Lallana and Ross Barkley vying for more attacking roles.