Multisite

Hello,
I have one question which is how can i change blogg-in.com/gold-rush-earners to gold-rush-earners.blogg-in.com.

I already checked “Before_You_Create_A_Network#Domain-based” and i figured out that i need to “creating addon domains or subdomains in cPanel or in a similar web hosting control panel”

It explain what method i should use but how WHAT are the STEPS!!
Help anyone please!