I'm confused in how I can add a new domain to my multisite,

I'm confused in how I can add a new domain to my multisite, I have installed domain mapping on my multisite http://www.365-promotions.co.uk & The new domain I have bought is http://www.365techies.co.uk
I have allowed support
Support access is ACTIVE until June 7, 2015 3:49 pm
Can you help me map the http://www.365techies.co.uk