They will sometimes send you emails. If you click on the little red button at the bottom of the email you'll get 5 points.
You can take advantage of those offers in the emails for more points.
You can sign up with companies for free trials, etc. for points.
You can purchase items from internet stores and get points for every dollar spent as long as you go through the My Points link first.
I believe it's 1,500 points to get a $10 gift card.
I've used My Points for a long time. When I cash out I get Web Certificates. I've saved for quite some time and put my Web Certificate balance toward our upcoming Disney vacation.
I hope that helps anyone who wants to know about My Points.