Everton can follow up their 2-1 victory over Wigan with further points against Chelsea this weekend.
Osman scored the Toffees’ opener in the win, which has seen Everton maintain their pursuit of Champions League football.
And the midfielder told The Independent that his side are in high spirits ahead of the challenge presented by third-placed Chelsea this weekend.
“It is always a little more difficult at Christmas time with people’s moods and the way the weather was, so it was a terrific three points to dig it out against a good Wigan side,” the Everton midfielder said.
“Chelsea are coming here on Sunday full of form now but we are confident and hopefully we will make a good game of it.
“We are certainly a developing team and have developed a lot over the last year or so.
“We are playing some good football and we tend to show that more when we play against the teams at the top end of the table.”
The Merseysiders occupy fifth position in the Premier League, level on points with fourth-placed Tottenham, and manager David Moyes is keen for his players to keep up the momentum for the remainder of the Christmas period.
“Over the Christmas period you are just trying to win the games and come out of the other end of it in no worse a position,” Moyes told The Daily Mail.
“We have six points from the two games and we might have settled for that at the start but we have now got another couple of games – Chelsea at home and then Newcastle away – and then you are probably talking about the Christmas period being over.
“We will try to take some points from them and keep moving up.”