First click on the Prospect tab.

Then click on the Prospect that you wish to add the reminder to.

You'll see the reminder feature on the right side of the screen between the Status and Tag section of information.

Click Add New.

Then type out the details of the reminder and select the day and time you wish to be reminded.

Click Add.

When the reminder is scheduled to come up the system will notify you via email and text message until you check the reminder off. 

You can check it off at the same location where you entered it.