acme.sh
A pure Unix shell script implementing ACME client protocol
...Just one script to issue, renew and install your certificates automatically. Does not require root/sudoer access. Docker ready. IPv6 ready. Cron job notifications for renewal or error etc. It's probably the easiest & smartest shell script to automatically issue & renew the free certificates. After the cert is generated, you probably want to install/copy the cert to your Apache/Nginx or other servers.