Tons of misspellings that cause syntax errors in the code above. This causes more problems than solutions.

RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^\.well-known/.+ - [END]

Correction to step 2)

Modify /private/etc/apache2/httpd.conf file:

##Change the following lines to the folder path where the web files are located:

DocumentRoot "/Library/WebServer/Documents/xxxx"
Directory "/Library/WebServer/Documents/xxxxx"

Here is what you need to do for OSX 10.14 Mojave:

1) Enable Apache on OSX:

# sudo -s
# cd /private/etc/apache2
# cp ./httpd.conf ./httpd.conf.bak
# apachectl start

2) Modify /private/etc/apache2/httpd.conf file:

## Uncomment the following lines:
LoadModule socache_shmcb_module lib/httpd/modules/mod_socache_shmcb.so
LoadModule ssl_module lib/httpd/modules/mod_ssl.so
LoadModule alias_module libexec/apache2/mod_alias.so
Include /private/etc/apache2/extra/httpd-ssl.conf
Includ /private/etc/apache2/extra/httpd-vhosts.conf
##Change the following lines to the folder path where the web files are located:
DocumentRoot "/Library/WebServer/Documents/xxxx"

3) Modify /private/etc/apache2/httpd-ssl.conf file:

# cp ./httpd-ssl.conf ./httpd-ssl.conf.bak

Add following:

Listen 443
SSLEngine on

##Change the following lines to the folder path where the SSL certificate and key are located:
SSLCertificateFile "/private/etc/apache2/server.crt"
SSLCertificateKeyFiel "/private/etc/apache2/server.key"

4) Modify /private/etc/apache2/httpd-vhosts.conf file.

# cp ./httpd-vhost.conf ./httpd-vhost.conf.bak

Add following:

<VirtualHost *:80>
  ServerName Server.domainname.com
  Redirect permanent / https://server.domainname.com
</VirtualHost>
<VirtualHost *:443>
  ServerAdmin admin@domainname.com
  DocumentRoot "/Library/WebServer/Document/xxxx"
  ServerName server.domainname.com
  SSLcertificateFile "/private/etc/apache2/server.crt
  SSLCertificateKeyFile "/private/etc/apache2/server.key"
  ErrorLog /private/var/log/apache2/server-error_log
  CustomLog /private/vart/log/apache2/server-access_log common
</VirtualHost>

5) Test the Apache configuration for errors after restarting Apache.

# apachectl configtest
httpd -v (Apache Version)

6) Restart apache.

# apachectl start / stop / restart

@MisterX

Great! Thanks for the useful feedback.