Scottish Labour leader Wendy Alexander has told party workers that they must help to expose the SNP.
She added that the fightback had begun since last May's election defeat and that Labour, "the people's party", would be the "people's defence".
Ms Alexander was speaking on Saturday afternoon at Scottish Labour's spring gathering in Aviemore.
Speaking at her first conference as leader, she said: "I will lead by exposing the dishonesty of the SNP."
Ms Alexander also outlined several policy reforms, saying children needed better rights - while admitting the Scottish Parliament's flagship free personal care for the elderly was not enough to help old people.
"I will lead by rebuilding Scottish Labour as a campaigning force," she told delegates.
"And just in case anyone's in doubt - I will lead Labour back to power in the Scottish Parliament."
Ms Alexander mounted a personal attack on the First Minister Alex Salmond.
She accused the SNP of breaking promises made to voters, but made no mention of the row over expenses to her leadership campaign last year.
The MSP for Paisley North said that the SNP had "promised a freeze in the council tax without cutting services and cuts have been introduced already".
Ms Alexander thanked former Labour first minister Jack McConnell - who was not present at the conference - for his work.
But she added that it was time for a new agenda which offered people in Scotland better life chances from the cradle to the grave.
She pledged to make Scotland the first country in the world to eradicate illiteracy, while providing nursery places to every vulnerable two-year-old.
Apprenticeships, she promised, would be provided to every 16 to 18-year-old who wanted one, with subsidies for small businesses to run them.
'The crofter pays'
The party would also look into personal care plans for those with chronic conditions, a new youth strategy and proposals to fight climate change.
Turning her attention to the SNP, Ms Alexander accused the party of pursuing populist policies in government which had led to spending cuts by Scottish councils.
She dismissed its "national conversation" on Scotland's constitutional future as "an invitation for every flag-burning blogger to rant and rave".
And she attacked the Holyrood government's plans to replace the council tax with a local income tax, telling the conference those living off unearned income would escape the charge.
She said: "The landowner will not pay but the crofter will. Hotel owners won't pay but hotel workers will. Stock market speculators won't pay but student nurses will."
Ms Alexander also warned the conference that the party must modernise its campaign strategy, suggesting more party members be given a say in policy-making.
And she questioned the practice of some election candidates being chosen by "only a handful of activists".
'Ten out of 10'
Ms Alexander told delegates there was still some way to go to help the vulnerable elderly live with dignity, adding: "It means admitting that delivering free personal care was not enough."
She went on: "Wherever possible, elderly people should be encouraged to stay in their own homes.
"It will mean more support for carers and better respite care. In care homes it means respect and dignity."
She concluded: "Here at Aviemore, the fightback has begun. It's time to go to work."
On Friday, the first day of the conference, Ms Alexander heard Prime Minister Gordon Brown praise her "brilliance and passion".
He said she would be the next first minister "whenever the next Holyrood election is called".
During a BBC Scotland news webcast, Ms Alexander scored herself "10 out of 10" for her performance as Scottish Labour leader.