Setting up PayPlans to redirect user once approved

Hi guys,

How do we go about setting up PayPlans to show when a user logs in for the first time, after being approved? We do not want to show users the subscriptions before they get approved as they might not get approved... so what we need instead is once a user is approved and receives the notification that they have been approved when the login to the site for the first time they're shown the subscription page where they select the most appropriate subscription and pay for their account. Once they have paid they will never see the payment screen again...

How do we do this?

Thanks,
Katie