The Spaniard comes in to replace David Moyes, and will attempt the slightly daunting task of installing his own philosophies on a side moulded a specific way for the past 11 years. Something new signings will help him achieve much faster.
For Martinez, the Toffees' notoriously frail financial state means it's more a case of manipulating the market instead of recruiting major signings—unless he fancies offloading a key player or two.
However, with no immediate fixtures, these are the first key actions Evertonians will judge him on, so it's important he makes a good impression and handles the major issues the right way. If not, they could come back to haunt him.
Here's a look at some of the biggest questions facing Martinez during this summer transfer window.
The first major problem for Martinez to contend with is Maroaune Fellaini, whose heavily rumoured buyout clause makes the Toffees powerless in preventing his departure.
This is not necessarily a negative situation. For while the Belgian is a leading player at Everton, his sale would generate substantial funds and provide Martinez with far more freedom in the transfer market.
However, the key aspect is time.
The longer this saga drags on, the more rushed the entire predicament will be and the less time Everton will have to identify and bring in suitable replacements.
It won't be easy, but any way Martinez can accelerate either eventuality will hugely benefit both himself and the club, which supporters will greatly appreciate.
The fact that it's not in his hands means Fellaini's destination next season won't affect Martinez's reputation. But the manner in which he handles the whole process, as well as the way he chooses to replace Fellaini if he does move on, will certainly be scrutinised.
Regardless of Fellaini's future, the primary issue for Martinez to address around his newly-acquired squad is in attack, where Everton are in desperate need of a reliable source of goals.
Ultimately, that was what cost them last season in their quest for Europe, with the rest of the Premier League's top seven sides scoring at least 11 goals more that the Toffees.
All of those squads had at least one striker in double figures, something neither Victor Anichebe or Nikica Jelavic managed to reach, which hampered their side's fortunes.
A new option up front is surely Martinez's chief objective over the coming weeks, and something that may well define his opening season at Everton.
Of course, the quality available to him will almost entirely depend on whether or not funds are brought in via sales. If they are not, while the Toffees may struggle to provide their new manager with substantial spending power, he will still be expected to locate a few solutions.
After Fellaini, the second most pressing issue concerning potential outgoings surrounds Leighton Baines. Although, unlike the Belgian, it's far more imperative the left-back is held on to at all costs.
Baines is one of Premier League's very top players and is integral to the Toffees' style of play. The fact he turns 29 at the end of the year decreases his value, making it far less worthwhile for Everton to consider letting him go.
Should offers come in, as many media sources strongly anticipate, Martinez must do his best to deflect them away and convince Baines his future remains at Goodison Park.
The fact Martinez was recently quoted by Sky Sports highlighting his desire to reward Baines' form with a new contract is certainly a positive start.
If Baines lines up for him next season, Martinez will undoubtedly earn approval from supporters.
Those first three points are Martinez's main concerns this summer, and the better he handles them the better his overall prospects should be at Everton.
However, he will also be looking at other areas of the team to improve on and may consider certain individuals as surplus to requirement.
Martinez has recently talked about bringing in two or three new signings, according to the Liverpool Daily Post, so it will be interesting to see exactly which areas of the team he targets.
One of these players will surely have to be a striker, but in midfield he could opt to recruit a passer who's more familiar with his possession-based style, or perhaps a more physical presence to solidify the Toffees' core.
In defence, John Heitinga could be one of those on the brink of leaving, while Jan Mucha's departure means Tim Howard is without any competition in goal.
How Martinez oversees these next few months will be crucial. Results distinguish a manager's tenure, but such is the importance some of these issues have on Everton's future that the correct handling will go a long way to extending his honeymoon period.