In Traffic you can create a list of actions which will appear on the right hand side of the diary page under the heading 'to do'

These actions are added when you have created a contact record against an individual and you have then set a follow up for a specific date and time.

To do this you first find the person you are wanting to make a contact record for and then click on the 'get in contact' button at the top of the page. Once the contact screen opens you can add any details you want to capture. This could mean that you are logging a conversation or you are sending an email. At the bottom of the contact window there are some fields for some follow up actions, select the relevant fields and set a follow up date and time and who the follow up is for. This will now appear in the users dairy.