Nowra Hill murderer Kim Leanne Snibson denied ever seeing her victim Kathryn McKay bound with rope, even when presented with a photograph from the post-mortem examination.

The 38-year-old broke down in the NSW Supreme Court yesterday when shown the picture of Ms McKay's burnt ankle wrapped in rope.

She had spent the morning repeatedly insisting that she was not thinking on January 28, 2006, the day of the murders.

She said she unquestioningly did as her accomplices had instructed her.

Snibson's answers to Crown prosecutor Paul Leask's questions were most often "I don't know", "I just wasn't thinking" and "I don't remember".

She pleaded guilty in May to kidnapping and murdering Ms McKay and her husband Greg Hosa but this week, during her sentencing procedure, she told the court she was not directly involved in the killings.

Snibson blamed her accomplice, Stacey Lea-Caton, 29, for the couple's deaths.

She said he flew into a violent rage during an argument Snibson was having with Ms McKay and Mr Hosa at her Calymea St house.

Lea-Caton was living in the house at the time.

Snibson said Lea-Caton killed the couple and threatened her to stop her going to the police.

When asked how decisions were made about torching Mr Hosa's car, using 44-gallon drums to hold the couple's bodies, taking the drums to Tomerong State Forest and setting them alight, Snibson said she either could not recall any conversation taking place, or that she just did as she was told.

"I wasn't thinking," she said. "I was scared or afraid. I just did what I was told."

Mr Leask put to her that she could not have been too afraid of Lea-Caton because after she left the forest, she went back to the Calymea St address, picked him up and the two returned to the forest to pour more petrol on the burning barrels.

"I just got him," she said.

"I wasn't going back out there by myself."

Snibson later said she had laid awake that night, not believing what had happened.