The former Barcelona manager has taken the reins from Jupp Heynckes, who led the Bavarian giants to a historic treble last season.
Lahm said that the Spaniard is "fine-tuning" elements of the team's style, but added that the changes are far from sweeping.
"Pep Guardiola has his own ideas," Sky Sports News quotes the 29-year-old as saying.
"He expects a few things from us, like the way we move or our passing and positional play.
"We're going to have to work on the fine-tuning in the coming weeks, but it's only about small things. We are not reinventing football."
Guardiola was announced as Bayern's next coach in January.