The Merseysiders managed a hard-fought win against a luckless Wigan on Boxing Day, a win that kept David Moyes' men joint fourth in the league.
Osman says he is confident the Toffees can make a good game of their weekend clash, and present the third-placed Chelsea with a different challenge.
He said: "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.
"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."
A deflected strike from Osman and a Phil Jagielka header gave the Toffees the lead against Wigan, and in a controversial incident involving the Everton defender, the Latics felt they deserved a penalty when Shaun Maloney went down under an Osman challenge, but referee Lee Mason did not give a spot kick.
Commenting on the incident, Osman said: "It is ultimately what the ref sees and the ref decided not to give it."
Osman, who won his first England cap last month, added: "If you've watched Wigan at all you'd know that they go and play their football and mostly outpass teams. We knew they were going to do that again.
"It is all about getting three points at the end of the day. We knew there would be times when we'd have to sacrifice possession but if we took our opportunities we'd be fine, and we did that."