The Dutchman took charge of his final match in charge of Ajax, who won the Eredivisie earlier in May, as they drew 2-2 with Vitesse on Sunday.
Ajax's squad are due to travel to Curucao, an island north of the South America coast, for a friendly against the national side as well as to fulfil sponsorship commitments before finally wrapping up their season.
However, Ten Hag won't be part of that tour having opted to step up discussions with the United hierarchy about their summer plans.
He will not officially start his Old Trafford reign until after the Premier League season ends.
But he is eager to get to work right away and will start preparations this week.
He could even be in attendance for Man United's final game of the season at Crystal Palace on May 22.
"Tomorrow there will be a party with the staff but I'm not going to Curacao this week," Ten Hag said on Sunday, having led Ajax to the title for the third time in five years.
"There is a lot of work that still needs to be done. I think that's understandable. This applies to every [new] club.
"A number of things still need to be organised with the staff and also with the squad. We will be working intensively on that from tomorrow."
The 52-year-old also sent a clear message to his new players when asked if he was ready for the 'sharks' in the media once he moves to Man United.
"I don't see them [the media] like that [as sharks]. I don't see you like that too, nobody.
"What it's all about is the dressing room, you need to be able to manage the dressing room. You have to make it function. That's how you win games."
Ten Hag is understood to have held several meetings with Man United's hierarchy as he prepares for his new post.
Former assistant to Sir Alex Ferguson, Steve McClaren, is set to join Ten Hag's coaching team at Old Trafford.
Although finishing in the top four is out of reach for Man United there's plenty to play for ahead of their trip to Selhurst Park.
Failure to beat Palace will give West Ham an opportunity to move into sixth and consign Man United to the Europa Conference League next season.