Hide the matches

If you have a child that plays with matches you want to fix it. You'll talk to the kid. You may read articles and books. You may discuss the issue with other parents, spend time in online groups, reach out in other ways. Some people in that situation will see the family doctor. A psychiatrist may be consulted. You will, almost certainly, look for root causes and try to find a long term solution. That only makes sense.

Before you do any of that, though, unless you are an absolute moron, you will hide the fucking matches.

Let me repeat that:

HIDE THE FUCKING MATCHES!