Common activities are activities that are not assigned to any project. These are created regardless of the project and can be standalone unlike earlier activities created under a specific project. It is optional to select a project for the common activities when filling the timesheets in common activities. To add common Activities below steps can be followed;
Step 1 - Select Time Tracking > More >Activity Info > Common Activities.
Step 2 - Click the Add button.
Step 3 - Give a name to the activity and click Save.