You can create a rule that drops a copy of a message you send into a specific folder after it has been assigned to a specific category. This can help you to remember to follow up on anything you are "Waiting for Answer" on.
You can turn on the "To-Do Bar" in Outlook 2013. It can help you quickly see what you have scheduled for the day. You have the option of showing a monthly calendar, the "People" pane, and "Tasks".