- Open the Remember The Milk web app.
- Click on 'Settings' at the top of the page.
- Click on the 'Reminders' tab.
- Make sure you have chosen when you want to be reminded.
- Enable 'Desktop Notifications' in the list of reminder methods.
- Ensure that the site remains open in a browser window.
Note: If you don't see Desktop Notifications listed, be sure you're using a supported browser (at least Chrome 20 or Safari 6).