Building new replacement site

I am in the process of building a new version of an existing site using the Source framework on the same server in a new subdomain folder.
The current address is https://dbtreecare.co.uk and I am building the replacement using the subdomain source.dbtreecare.co.uk with the site inside a folder named “source”

Does anyone have any tips on when the time comes to replace the existing site with the one on the subdomain. Is there a particular procedure?

Thanks Fynn for that.
I’m using Go CMS Unlimited for the blog and 1LD’s Quick Editor for the CMS and Repository with Gallery 3.

For goCMS

Thanks for that. I have just tried goCMS but have decided to go with Armadillo as I really like the Redactor editor interface.