sure its simple to

Hello,
In writing test cases to test applications software the 
test cases are defined by looking through the Business 
Analyst documents called the Design Specs and the Detailed 
Design Specs.  (Also called the External and Internal 
Design Specs).  Every requirement within the specs should 
be identified and written down as each of these will become 
a test case item.  The test case then is written so that a 
person running the test will perform a series of test steps 
so that each requirement is tested.  The test cases should 
be reviewed by the Business Analyst prior to use to verify 
that the test will actually verify the requirement being 
tested.

The test case should include at minimum the following:
A Header section with the following items:
Project Name
Test Case Description
Module Under Test
Version/Build Number
Test Case Number
Setup for Test Preconditions
Test Case Written By
Tested By
Test Date
A Test Steps section with the following items:
Test Step Number
Test Step Action
Expected Results
Actual Results
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