To clone a Project, navigate to the Project page, then click the clone symbol to the right of the Project:

From there you need only modify the details as desired to clone your Project.

When you create a clone, date variables will be used in the title. In the example below, you can see {mm} and {dd} standing in for the month and date the clone was created. This will help you differentiate your cloned projects.

You can also omit certain details from passing through to your cloned project by choosing the 'More options' button. This allows you to exclude things like Tasks, Tags, and Task Rates.