How to make domain name in apache2 on linux

1.  go to /etc/apache2/sites-enabled and edit  000-default.conf input like example on bottom

#start hire

<VirtualHost *:80>

        ServerName www.example.com

        DocumentRoot /var/www/html/foldername

</VirtualHost>

#end hire

2. go to /etc and edit hosts (do this # sudo nano /etc/hosts)  and input this

127.0.1.1   www.example.com

that mean is 

you web in your localhost name is www.example.com ,

runing on port 80 and locate in /var/www/html/foldername

Done ,. i hope i help someone