Before creating any report in report net make sure you are have the planning information you need.

Creating a report involves following steps:

• Specifying a package
  Choose a package through cognos connection>report studio>Select a module from the list.
• Choosing a report template
  Create a empty report first,click one of the predefined report templates ,click OK.
• Adding query items
  In the insertable objects plane,select the query item that you want to add to report,drag it to the desired location.
• Saving report
  Save the report from file menu.
• Running the report
  Open the report that you want to run.
  From the Tools menu, click Validate Report.
  A message box appears indicating whether any errors were found in the report.
   If you want to enable Design Mode Only filters defined in the package, from the File menu,
  click Use Model Design Filters.
  Use these filters to limit the amountOpen the report that you want to run.
   From the Tools menu, click Validate Report.
  A message box appears indicating whether any errors were found in the report.
  If you want to enable Design Mode Only filters defined in the package, from the File menu,
  click Use Model Design Filters.
  If you want to set run options, from the Run menu, click Run Options.
  From the Run menu, click one of the options to produce the report in the format you want.
  You can produce a report in HTML, PDF, CSV, XLS, or XML.