I have created a new command but it does not appear in the menus or the toolbar?
Just creating the command is not enough to make it visible. Commands only become visible in pop-up menus, toolbars or on menus when they are enabled within (i.e.: associated with) an object (the Framework, an application, a business object or a business object instance).
To add a command to a menu in the menu bar, use the Menus… or Commands… option of the Framework menu.
To enable a command double-click on the object and select the Commands Enabled tab.