Stay up to date with patches and updates

As with any computing device, your router has special operating software called firmware. Most commercial companies will release patches or updates to that firmware. While these are not frequent, they can often fix security vulnerabilities in the hardware. You can likely check for updates in the router administration area.

Another effective practice is to ensure all updates and patches are applied to the devices connected to the network. Gaining control of one device on the network, especially an older, forgotten machine, gives an attacker a foothold to move on to other, more valuable targets. If you're not using a computer or other device, turn it off, or at least disconnect it from the Internet, if possible.