Adding actions to a project
Add actions to a project whenever you think of something that you need to do in order to move the project forward.
To add an action to a project:
Make sure you are in planning mode; the view switcher in the toolbar should have the Planning icon highlighted: 
Select the project, either in the sidebar or in the main outline, by clicking the index-card icon next to its name. Or, select an already-existing action in the project.
Press Return or click the Add Action button in the toolbar; the new action appears immediately after the item you selected.
Type a name for your new action.
You can move an action between projects by clicking its bullet and dragging it to its new location. You can even turn an action into a project by dragging it to the top level of the outline or the sidebar.