How do you secure an ASP.NET folder by Role?

I am using Forms Based Authentication. I want to implement this:
<location path="~/SavAdmin"> <system.web> <authorization> <allow roles="Savitas Admin"/> <deny users="?" /> </authorization> In other words, I want only people with Roles of "Savitas Asmin" to be able to have access to that sbfolder. I don't know if I need to implement Membership or Roles. I don't see the Web Site Administration Tool anymore in VS2013 to define Roles, etc. Can I get some basic help?