The new Home Office-backed youth advocates programme is already equipping local role models in London with key skills, according to a statement.
Topics including safeguarding, defusing conflict and substance misuse, are aimed at helping them spot warning signs and to offer guidance on how to cope in challenging situations.
The details were unveiled at a Serious Violence Taskforce meeting chaired by home secretary Sajid Javid this week.
To support the advocates' conversations with young people, adverts featuring the #knifefree hashtag will run in key London and Manchester areas.
Javid said: "Intervening early in the lives of vulnerable youngsters is key in combating the rise of serious violence.
"It's therefore vital that we communicate with them directly through the people in their communities who they respect and listen to.
"That's why the grassroots advocates programme and our #knifefree campaign are integral to the work we are doing to stop this bloodshed."
The youth advocates in London, who work in key community focal points such as boxing clubs, youth centres and schools, have already started training. The programme in Manchester will start in the next few weeks.
The campaign focuses on young people who have turned away from crime thanks to a mentor in their community.
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Taskforce members were also briefed on a connected collaboration with youth channel SBTV, which has launched two new videos on You Tube.
The films were shot across the UK and show music artists speaking to young people from their area about being knife free.
These use music artists, such as Bugzy Malone, who has almost one million Instagram followers, to help reach the widest audience.
The campaign - which aims to educate 10- to 21-year-olds on the dangers of carrying knives - is one of the 61 commitments in the government's Serious Violence Strategy, which stresses the importance of early intervention and help young people build resilience.
Knife crime was also on this week's agenda for London mayor Sadiq Khan, who has announced that offenders will be GPS-tagged upon release from prison in a one-year pilot scheme.
The initiative will begin in four boroughs most affected by knife crime: Lewisham, Lambeth, Croydon and Southwark.
Assembly member Steve O'Connell, who is chairman of the assembly's police and crime committee, said members would be "monitoring the effectiveness going forward".
"Many different measures must be taken in the fight against violent crime," said O'Connell.
"Dealing with reoffending is important, but it is equally critical to prevent young people from picking up a knife in the first place.
"We still await details on what the new Violence Reduction Unit's aims and targets will be.
"The committee strongly recommends that prevention should be at the front and centre of its plans."