Malcolm Turnbull campaigns for Liberals

Malcolm Turnbull has been out campaigning for the Liberals in the NSW election, saying it was "so important" the Berejiklian government be re-elected.

The former prime minister spent Saturday morning with Coogee MP Bruce Notley-Smith at a polling booth in Sydney's eastern suburbs.

The electorate takes in part of the federal division of Wentworth, Mr Turnbull's former blue-ribbon Liberal seat that fell to independent Kerryn Phelps in the October by-election.

"It's so important to re-elect the Berejiklian government and Bruce Notley-Smith right here in Coogee," Mr Turnbull said in a video posted on Twitter on Saturday.

The dumped Liberal leader wrote a glowing opinion piece about NSW Premier Gladys Berejiklian in The Sydney Morning Herald, describing her as practical, competent, smart, humble and a great listener and learner.

"And she gets things done," he wrote, echoing the Liberals' campaign slogan.

Mr Turnbull said Ms Berejiklian had no appetite for the nasty side of politics and labelled her government as the most successful state government in Australia.

"But there is a lot more to do. And Gladys Berejiklian is the leader to do it."