Once you have identified the activities you'd like to begin tracking you can start creating your activities in Salesforce. Navigate to the 'Message Actions' tab under 'Application Settings' within the Act On It Lightning App: 

Click 'New' in the top right. Leave the record type as 'Act On It Template' and select 'Next'. Select the 'Activity Tracking' option from the list of available templates and click 'Next':

Complete the form as follows:

• Action Name - The name of the activity at it will appear in the Event Timeline e.g. Phone Call, Deal Pushed, Web Visit (etc).
• API Name - The unique developer name for the activity. Store this value for later as it will be referenced in the automation used to log this activity.
• Description [Optional] - Optional description. We recommend using this to explain what the activity signifies. This value will appear against the activity in the Event Timeline (via hover).

Choose a suitable icon and icon color. This icon will appear in the Event Timeline. 

Click 'Next'.

Lastly, choose a compatible data type. Most standard and all custom objects are supported. The data type refers to the type of record the activity will be related to. For example, our call logging activity is triggered by the creation of a 'call' task. However, we want to log the call event against the related opportunity (to appear in the opportunity event timeline), so we'll select 'Opportunity' from the list of available options:

Click 'Save' and your action is now ready. Next we'll explore how you can define relationships between activities.