There are multiple factors contributing to high murder rates:

• Guns: ban them.
• Mental health: provide free support for mental health issue, including a phone number where people can safely report friends and relatives in crisis. Today if you report, they send police officers totally untrained and unprepared for these situations and that easily ends up in drama
• Gangs: a lot of the murders are gang members against gang members. There is no miraculous solution to that. But I would advocate: decriminalize possession of small amounts of drugs, provide shooting rooms with support (both physical and mental) freely available. I would even support offering drugs substitutes for free under control. If the drug price collapses, their business collapses.

So: vote for someone who will support social science based policies.

I'm sorry there are no easier way. "Get tough on crime" is the solution that was experimented the most and has proven again and again to be inefficient.

Edit: you may already be doing that, don't take this as an assumption you don't. I understand the frustration and that feeling of being powerless while people ask you "why aren't you DOING something about it?".