If the Resourcing Mode is set to Strategic Planning for your Login Group, a Resources pane shows supply allocations for each listed resource and the breakdown of supply to projects:
Here you can:
•drag the assigned supply to a different period for a resource
•reallocate project supply between resources for the displayed periods by dragging the project name onto another resource
•for a Resource, click 
to the right of the resource name and choose:
o Create a New Assignment. This is restricted to projects that are set as ‘Assignments affect Strategic Availability’
o Add Supply to supply a resource
o Show Resource Details to see full details of the selected one.
•for project supply, click:
o the project name to change the supply for a period:
o 
to the right of the assignment name and choose:
— Open Supply to edit the project supply
— Move Supply to bring forward or delay supply by a number of weeks from a specified date, for all or selected resources
— Delete Supply to clear the entry.