December is likely to be the busiest month of the campaign, with a total of nine matches in 31 days.
City have already beaten Bournemouth and Watford this month, but with seven more games to come in the space of 23 hectic days around the festive period.
“We’re entering into a very demanding month, with games every three or four days,” said Otamendi.
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“The most important thing is trying to recover well after the games.
“Obviously, the physical effort and the fatigue will be there, but we have to keep paying attention to the small details that make the difference and help to win games.
“December is very important due to the huge amount of games and creates a difference on the table.
“If a team manages to get a big amount of victories and points increases heavily their chances to be champions at the end of the season.
Otamendi, who made his 100th Premier League appearance for the Blues at Watford, is having to be more patient for game time this season due to the form of John Stones and Aymeric Laporte.
When he has played, the France defender has generally been his defensive partner and Otamendi has been impressed by Laporte’s form.
“Last season I played more with John and Vincent. We are four central defenders and every one of us can play to a great level.
“I always try to be professional to try to be in the best shape as possible when I have my chance to play.
“It’s true that last season I had more minutes, I was one of the ones who played the most minutes. But I always try to be professional and give the best I can.
He also added the Blues’ miserly defensive record is a collective team effort and one that the defence can’t totally claim credit for.
“Goal difference could be very important at the end of the season.”