Help with uploading script to hostgator

Can anyone please help. I have uploaded a script to the public_html ok. I have uploaded it to the name I want. I now need to run setup. How do I do this. It says for example. my.domain.com/articles/setup.php
With hostgator do I put my main domain first and then add on or what.
I logged on with my main name and then uploaded to the new name that had nothing in the public_html folder.
If this is making any sense please help.
Thanks

 

Are you using subdomain.domain.com or just domain.com ?

 

I have just sent the name to Hostgator and want to use domain.com. I have added a my sql name and am not sure what else I need to do.Usually if I use a new domain with a blog I use domain.com