Martinez has already brought in Romelu Lukaku and Gareth Barry on a permanent deals after successful loans at Goodison Park last season, while Bosnian midfielder Muhamed Besic and young defender Brendan Galloway have also arrived on Merseyside this summer.
Martinez admits their transfer business will depend on the fitness of duo Arouna Kone and Bryan Oviedo after they suffered long-term injuries last season.
"Towards the end of last season I said we needed six more players, but it wasn't six new players, it was six players," said Martinez.
"We have added Barry, Lukaku and Besic and we also have Tony Hibbert who re-signed.
"We still need one or two, depending on how quickly Arouna Kone and Bryan Oviedo recover from their injuries."
Meanwhile, Martinez admits he is not sure if Lukaku will be fit for the start of the season due to the after-effects of his participation at the World Cup with Belgium.
Lukaku, who is Everton's record signing after sealing his move from Chelsea earlier this month, only returned to training this week and he will not feature in Everton's final pre-season game against SC Paderborn on Saturday.
Martinez insists he will not take risks on the fitness of Lukaku or his fellow Belgian Kevin Mirallas.
"When you have players coming back from the World Cup you have to decide if you want the players straight away or do you give them a bit of time to refresh and be ready to play for 10 months?” added Martinez.
“It will only be Kevin Mirallas and Rom who might not start the season. For Romelu, it will depend on how he adapts to work from now until August 16.
“There is a degree of risk if you put them into a situation so early. They’ve been training really well and are accumulating a lot of work.
“Playing in a game would have stopped them being able to get in a lot of that extra work and we didn’t want to do that.
“They’re not going to be a part [of the team] but they will get three sessions in while we’re out here.
“That will accelerate the process of them being ready as quickly as possible