To create Trade Orders first you need to add Symbol you want to create trade order for. See Adding Symbols to Trade Grid.
Click on the C (Cancel).
Order cancellation request will be sent to your broker. Status column will show current order execution state.
Right-click on the corresponding Trade Order row to show context menu.
Select Cancel from context menu.
Select corresponding Trade Order row by clicking on it or using Up/Down keyboard keys.
Press Del key.
Right-click on any Symbol or Empty row where you can add new Empty row.
Select Insert Row from context menu.
U.S. Securities and Exchange Commission notes on:
Learn how to: