Roy Hodgson's side have spent time in the Algarve, Miami and Rio de Janiero to prepare for the tough conditions of Manaus, where they will play Italy in their opening Group D game on Saturday.
England have also played three warm-up matches against Peru, Ecuador and Honduras and left-back Baines reckons they have had the ideal build-up to the tournament.
"I don't think it could have gone much better to be honest," said the Everton star.
"It's been really enjoyable, we've got some really good work in and spent some good time together.
"The preparation in terms of the heat and the opponents has been really good. For the time I've been involved with England, this is as good a group as there's been.
"There's a real good spirit throughout the camp and part of that is probably down to the preparation we've been doing.
"We've been working hard but have obviously been spending a few weeks together that has enabled us to get that kind of club feel to the international set-up."
While the preparations may have been impressive, Baines knows now they have to translate that positive work onto the field against Italy.
"We're looking at Italy and being prepared for what they may have, but we're focusing more on what we can do," he said.
"I think they'll be doing similar things. There will be a lot of players in our squad that they'll be doing their homework on and trying to make sure they've got ideas on how to stop them.
"You know what to expect from a side like Italy, they are one of the top sides in the world, full of good footballers and they've tended to play in a certain style for a number of years, so we are preparing for that.
"We're looking forward to the game. We were talking before about the weather and things like that, but I don't think there's anyone who is really going to get an advantage from the weather. It's going to be more or less the same for both sides."