Here are 10 issues which should be at the top of his to-do list when he starts work at Carrington.
1. Win the dressing room: Unreserved faith and support from United’s senior players will be imperative for Van Gaal to work in the right kind of atmosphere at Old Trafford, something his predecessor David Moyes apparently lacked.
It will also help if he sees things eye-to-eye with his assistant Ryan Giggs, who should play a crucial role in bonding the dressing room with the iron-fisted Dutchman.
A healthy relationship between the coach and the players is the basic prerequisite for United to restore the Alex Ferguson-era confidence that was so palpably shattered by poor results under Moyes.
2. Quality signings: Luring top names to a club missing out on Champions League football is not an easy task but Van Gaal will quickly have to identify his transfer targets and splash out a considerable amount of money to sign them.
With United set to lose 30 million pounds ($50.4 million) in revenues after failing to qualify for the Champions League or even the second-tier Europa League, there is no room for flops such as Marouane Fellaini, who joined last year from Moyes’s former club Everton.
3. Sort out the defence: United’s back four looked very fragile under Moyes, with ageing stalwarts Rio Ferdinand and Nemanja Vidic struggling to perform to their former capability.
With the latter off to Inter Milan and the former also on his way out of Old Trafford, Van Gaal may be forced to turn to Phil Jones, Chris Smalling and Jonny Evans, none of whom has convinced at the heart of the backline.
In all probability, the coach’s first priority in the transfer market will be to find a top central defender who will shore up the leaks. Left back also appears to be a weak link with Patrice Evra uncertain about his United future and Alex Buttner short of experience and quality.
4. Midfield: Juan Mata will certainly add bite up front in an attacking midfield role but United are still craving for a playmaker who acts as a link between defence and the forwards.
While Michael Carrick has done a decent job as a holding midfielder protecting the back four, his limited mobility and lack of thrust was always a glaring chink in United’s engine room after Paul Scholes stopped pulling the strings.
Signing a top name in this department will be another challenge for Van Gaal, who will also have to make the best use of Mata and Shinji Kagawa while hoping that the much-criticised Tom Cleverley can make substantial progress.
5. Revert to attacking football: Van Gaal’s philosophy is a perfect match with United’s long-standing strategy of always taking the game to the opposition, even if it sometimes meant risky attacking.
This trait was lost in big games under Moyes, notably in the Champions League quarter-final against Bayern Munich and clashes with top Premier League rivals Manchester City and Liverpool.
United looked completely at sea in a cagey formation and reports that the players never came to terms with it fuelled Moyes’s abrupt departure after only 10 months in charge.
6. Decide where to use Wayne Rooney: Having secured Rooney’s long-term future at the club, United will hope that the 27-year old will fire on all cylinders next season as the club aims to climb back into the Premier League’s top four.
Van Gaal will need to decide whether to use him as a “number 10” or an out and out striker, as Rooney can operate effectively in both positions.
His finishing needs to be more clinical for a striker and he also lacks the subtlety of an Alessandro Del Piero or Francesco Totti in a deeper role.
But if he is used consistently in a single position instead of being moved across the front line, Rooney could deliver under Van Gaal.
7. Move out of Ferguson’s shadow: United’s most decorated manager made it no secret he wanted Ryan Giggs to succeed Moyes after his temporary four-match stint as interim manager but the board went for Van Gaal and his impressive track record.
While Moyes was always going to be in Ferguson’s shadow, not only for the fact that the fellow Glaswegian watched his plight from the directors box, a man of Van Gaal’s ego and principles will accept nothing less than being his own man in every way possible.
Hence he might want to make clear to the players, staff and perhaps even the power corridors that the unprecedented haul of silverware under Ferguson is a bygone era meaning and that United have it all to do if they are to restore the fear factor among their rivals.
8. Handle the media: Being a United manager can be one of the most unforgiving jobs in football as Moyes found out and his plight was partly rooted in a seemingly uncomfortable relationship with the media.
Much like Ferguson, Van Gaal has the uncanny ability to dominate the press room and when the going gets tough for him at Old Trafford, he will need this acquired skill to stand firm in the line of fire.
9. Be honest with the supporters: The United faithful were determined to back Moyes and answer Ferguson’s appeal in his farewell speech to “do your job and support the new manager”.
However, they became increasingly disillusioned not just by the poor performances and results but also Moyes’s refusal to admit the shortcomings of his team. He frequently said in post-match interviews after defeats that he thought his side had played well and had simply been unlucky.
But the fans were not fooled and Van Gaal must be more honest in assessing the team’s failings and convince the supporters quickly that he knows how to rectify them.
10. Be your own man: Moyes seemed constantly torn between respecting the attacking traditions of United as a club and his own more conservative and pragmatic style which had served him well at Everton.
He admitted he was reluctant to take off a clearly struggling Robin van Persie as United tried to overturn a 1-0 deficit at Old Trafford against Newcastle because off what the supporters would think.
Ferguson made many unpopular decisions during his reign and was usually proved right in the long-term. Van Gaal must do the same.
($1 = 0.67 British Pounds)
(Writing by Zoran Milosavljevic, editing by Ed Osmond)