What can ordinary people do to help in the fight against crime?

In my opinion,I think that Crime and the fear of crime in a community is, of course, a real and prevalent problem in today's society. But that does not mean that there is nothing ordinary people can do to prevent it. No sensible person would advocate vigilante-ism but there are many steps people can take to prevent crime in their community. for example neighbourhood watch schemes,take responsibility and don't be afraid.

After all prevention is far better than cure, and never more so than in these circumstances. So, if people turn their minds to crime and the fear of crime they may wonder how you can help prevent crime in your community.
Call the Police when they see someone break the law. Give a good description of the bad guys and direction of travel.

If you want to protect yourself then yes get a concealed carry permit and carry a gun. However, that is not going to help the Police catch criminals. That will just help you not be a victim.
All that is necessary for the triumph of evil is that good men do nothing.
Get a conceal carry permit. Watch your surroundings closely. If you see anything suspicious call the police. Start a block watch or recruit many people to walk the neighborhood so you can keep an eye out for any crime in progress. Some people actually set traps for thieves.

the best solution is to raise children to be law abiding and to be honest people
very hard thing to do but back to the basic do unto others what you would like them to do to you.