To assign a shortcut key to the command put the cursor in the Press new shortcut key edit box and press the desired shortcut key. Quick typing of mathematical and other symbols. How to Create a Shortcut to a File or Folder.
Right-click the Sigma button choose Properties and click Keyboard.
Place the cursor below the column of numbers you want to sum or to the left of the row of numbers you want to sum. Click the Layout. The words Create Link in Desktop will appear. To create a desktop shortcut to a file first locate the file somewhere in File Explorer.