Help with roles in SQL Server Reporting Services 2005

I know how to create roles but how do you add users to them, and then roles to different levels? This section of MSDN doesn't tell much

http://msdn2.microsoft.com/en-us/library/ms157397(en-US,SQL.90).aspx

You add users to the roles by navigating to the item you wish to secure. You then click on the property tab, then the security sub-tab. From here you can click on 'New Role Assignment'. Now you can add a user or group and assign the role you wish for them to have on this item.

You can also do this at the site level for the site level permissions. Click on 'Site Settings' in the upper right hand corner. Then click on 'Configure site-wide security'. From here you can again add users and assign them different system roles.

-Daniel