How do I point a domain to a sub-domain of another site (different hosting provider)?
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I am fairly junior in web dev, and have a bit of a puzzle. I will try to be as clear as possible about the problem, but would really appreciate any help!!

I have been developing a site using Drupal for a local charity. They already have a site on domain (lets say): "www.charity.com"

The domain and hosting for this site is under the control of someone else who helped the charity many years ago.

In order to develop the new site, I created a sub-domain on the domain I owned through my hosting provider (lets say): "www.dev.mysite.com"

I have now completed the dev, and want to tell the guy managing the old charity site what changes he needs to make to point www.charity.com to the subdomain i am hosting...is this possible? What is the best way of doing this??

Also, in about 8 weeks time, I am going to be able to acquire the domain for www.charity.com, so am happy with temporary measures if need be as can resolve it properly when I own the domain...

Thanks in advance for any help..

Andrew