Generate and install SSL certifcate using Certbot:

1. Install Certbot from FreeBSD ports and install python:
   cd /usr/ports/security/py-certbot
   make install clean
   cd /usr/ports/lang/python
   make install clean
2. Generate a free SSL
   certbot certonly --webroot
   
3. Enter the web root and hostname for certificate
4. Make change to Apache configration and restart Apache
5. Add the following command to cron and run once a day
   /usr/local/bin/python -c 'import random; import time; time.sleep(random.random() * 3600)' && /usr/local/bin/certbot renew

Uninstall an existing SSL certicate generated by Certbot:
certbot delete --cert-name ssl.example.com

where ssl.example.com is the sub-domain that need to be removed.