New AgeInstalled Lynis, a security auditing tool, on my Linux laptop to check the strength of my security settings. Got a "Hardening Score" of 69 *snicker*
The report gave a lengthy output with suggestions for improving security.
I modified a bunch of secure shell settings (sshd, used for remotely logging in) per the Lynis report suggestions, and also installed rkhunter, a root kit and malware checker (none detected). My new hardening score for my Linux laptop is 76.
Many suggestions remain to be tried (not all are applicable) to increase hardening. Both Lynis and rkhunter are free tools.