There are two ways to do this.
Adding a Team Member to a project
Step 1 Go to Projects Page
Step 2 Click on Team against the project to which you would like to add the new employee.
Step 3 Unselect the checkbox “Show selected Employees”
Now you should be able to see all the employees available in your account.
Step 4 Add the new new employee to the project eam and you are done.
Adding a project to an Employee.
Step 1 Go to Employees page
Step 2 Click on projects against the employee name whom you would like to add to a project.
Step 3 Select the check box against the project to which you would like to add this emplyee and you are done.