XML schema for XML reports on SQL Server reporting services

This may be a newbie question, and I have done quite a lot of searching for an answer but have had no luck.

I am using SSRS on SQL server 200r2 (standard edition) to generate XML reports. I have developed my report in Report builder 3 and uploaded the report to the Report server. So far so good Now I want to have a subscription that generates the reports in XML format and deposits it into a folder No problem with this straight forward enough

How do I install an XML transform or specify the actual XML schema for the rendered document as I don't want to manually handle the generated report.

In the Report Builder software there appears to be a report property where I can specify as path which would have to be to a file on my local desktop but nothing on how to supply a similar file to the reporting server to use.

How do I do this? and I thank all of you kindly stackoverflow souls in advance for your collective wisdom.