I presume you mean after CAESAR II recommends load cases?

Modification of load cases is rather simple. You can use the toolbar buttons at the top of the dialog to add or delete rows. For new rows, the primative loads (listed in the left hand box) can be dragged and dropped into the load case. In the right-most column, use the drop-list to select the stress type.

If you have a project with multiple job files that share the same set of loads and load cases, you can import the modified loads from one job to the next - using the [Import Loads] button.