1. Login to your Ubuntu Server, navigate to and list »sites-available« directory

cd /etc/apache2/sites-available 
ll

2. You should see the files:

000-default.conf
default-ssl.conf

3. Disable the default site configuration

sudo a2dissite 000-default.conf 

4. Create a copy of the default configuration file and open it for edit

sudo cp 000-default.conf yourdomain-com.conf 
sudo nano yourdomain-com.conf 

5. Enter the configuration (you can delete the comments) in this manner

<VirtualHost *:80>
ServerName yourdomain.com
ServerAdmin info@yourdomain.com

DocumentRoot /var/www/yourdomain.com

ErrorLog ${APACHE_LOG_DIR}/yourdomain.com-error.log
CustomLog ${APACHE_LOG_DIR}/yourdomain.com-access.log combined
</VirtualHost>

6. Save and exit the file edit mode

7. Enable the yourdomain.com site configuration

sudo a2ensite yourdomain-com.conf 

8. Be sure to create appropriate directory and set permissions

cd /var/www/
sudo mkdir yourdomain.com
sudo chown username:username yourdomain.com -R

(use your own Ubuntu Server username)

9. Reload Apache2 server

sudo service apache2 reload