If you followed Jeffrey Way's way ;-) outlined in that two-part miniseries: https://laracasts.com/lessons/build-an-activity-feed-in-laravel then you should have by now trait that hooks up to your model events. As far as I remember he also used polymorphic relation table. Now what you need now is to hook up to the events you need to listen to:
- auth.login - fired when user logged in successfully
- auth.logout - fired when user logged out
And here in docs is an example how to make an event subscriber class: http://laravel.com/docs/5.1/events#event-subscribers All you need to do is make those listeners that insert a record to your "activity" table.