Plugin Main Site Only

Hi all,

I downloaded a plugin that I only want to activate on the main site that I am hosting and not all of the potential sites people may sign up for via multisite and supporter.

If I network activate it makes it available to all, but if I deactivate it allows it to be made active by site admins.

This may be a dumb question, but how do I get plugins to just go to specific site(s) rather than all?

Thanks.