Hello,
Well first you have to have a provider to host your project and it will redirect to your domain "www.mysite.com".
If you do not choose Azure and hire any other hosting provider, the easiest way is to give a "publish" of your aspnet application to a windows directory, there it will put your files ready for publication.
To publish, you must have an FTP address that your contracted provider will provide, and with this access, through an FTP program, simply connect and send your files obtained by "Publish" to the directory of your provider.
Briefly this is the simplest way. Of course, if it was developed to host in azure, the path is different, it goes on in the answer above, but Visual Studio automatically connects and publishes your application there, just connect to your account through Visual Studio, this is very simple, but give the publish indicate that it will be in the Azure.
Of course when hiring the hosting, it should be configured for asp.net, and inform the framework that this your application, then first check the framework that your provider provides and build your application for this framework.