I installed membeship and chose the papypal payments gateway, but nothing is appearing on my groups?

Membership and its payment gateways:
I installed membeship and chose the papypal payments gateway, but nothing is appearing on my groups page which will enable someone to sign up for my groups.

Easy Paypal Payment or Donation Accept Plugin:
I did some research and found this plugin, which I installed hoping it would be a good substitue, but cannot tell if the plugin will only allow access to my individual groups as it shows up on all of my pages in the sidebar.

I would prefer to use the membership plugin if possible, but can't get the sign up or register now button to appear on my groups page or any other pages for groups specifically.

Can you help?