The 32-year-old signed a season-long loan with the Toffees late on transfer deadline day after falling out of favour at Manchester City.
The former Aston Villa midfielder had been told by new City boss Manuel Pellegrini that he did not figure in his first-team plans and as such has not made a single appearance so far this campaign.
Despite the lack of matches Barry insists he has been keeping himself fit and is ready to start for his new club against Jose Mourinho's men on Saturday - should he get the nod from boss Roberto Martinez.
"It's a fantastic first game to potentially be involved in but it's the manager's decision because I have not played loads of minutes at the moment," he told the club's official website.
"I feel fit. I haven't missed a day's training and I featured in bits and bobs of the pre-season games.
"The season's a well underway now and I've not played but I am confident if asked to play I can do a good job."
You can follow Everton v Chelsea on Sky Sports 1 from 17.00 on 14 September