The best way to segment your Projects into a phases is to use Milestones. With a start and due date, Milestones can mark important stages of a Project:

To see individual Milestone details, click the Arrow Icon and you. The main reason why Milestones are so convenient for segmenting a Project, is because you can have any number of Discussions, Files, Notebooks and Tasks filed under a Milestone and keep all the important information related to that Project phase.

Milestones can be organized in the following ways:

• Rescheduling - enables you to change the start and due date of your Milestones. Drag the Milestone Bar to desired date on the timeline. After confirming the new date range, choose whether to reschedule all successive Milestones or manually select some of them.
• Reordering - use the Reorder button in the top right corner of the Milestones page to change the the order of Milestones with the same start date.