Instead of exposing the camera directly to the internet via port forwarding, set up a VPN on your router. This way, you have to "tunnel" into your home network before you can see the camera viewer [6].

Never leave the factory settings intact. Use a strong, unique password for the camera’s web interface.

Many routers and cameras have UPnP enabled by default. This allows the camera to automatically "punch a hole" through your firewall so you can view the feed from your phone while away from home. Unfortunately, it also makes the camera visible to search engines like Google or Shodan [5].

Turn off UPnP on both your camera and your router. If you need remote access, use a more secure method.