NEW YORK — “I do one thing at a time, and I couldn’t possibly have been thinking about anything else while making this movie,” said Nancy Meyers, seeming particularly calm, cool and collected for a helmer who had just finished post-production on her latest pic, “The Holiday” just a week before its debut at the Ziegfeld.

The in-demand Meyers hasn’t even begun to decide what pic she’ll move to next. Following the preem, the helmer was busy powwowing with Sony brass — including Amy Pascal, Jeff Blake and Michael Lynton — at a Museum of Modern Art after-party that turned the lobby into a clubby lounge.

Now that “Holiday’s” in the can, Meyers will next have to see how it fares in a December crowded with holiday pics. “I go into a marketing meeting and there are all these people, and a bulletin board, and you just think, ‘Oh, no!’ ” she said.

Sony — which has “Casino Royale” in current release — is certainly hoping that the pic is another stocking stuffer come Christmas time.