how to set subdomain on phalcon application

I link main domain on application example www.example.com and i want to link my subdomain on phalcon admin site like www.example.com/admin ... how i can do it ? when i open admin.example.com it open the www.example.com/admin using rewrite mode.

i am using apachi 2.4 server on windows server hosting

how i set my application for main domain and its sub domain for admin panel