First timer setting up web domain

I  took over a company who has several domain web addresses, right before my predecessor left he purchased the new corporate office domain name. Both old and new domains names will be active and my developer is creating a page now and has asked me for our new domain web name.

I know where it came from but have no clue how to activate it or point it to my iis server.  Then I need to create a sub-domain off of that. How do I do this?

Any suggestions are most welcome because I have never done this before.

Thanks

normally would run their own nameserver(s) -- that's DNS -- for your domain. You need to ask them to assign the domain to one of your company's IP Addresses. This is a very common request so you don't need to worry about asking them to help.