To use AutoCAD ActiveX Automation effectively you should be familiar with the AutoCAD entities, objects, and features relating to the type of application you are developing. The greater your knowledge of an object's graphical and nongraphical properties, the easier it is for you to manipulate them through AutoCAD ActiveX Automation.
Remember that the AutoCAD ActiveX Automation Help file is available—just press F1. If you are having trouble with a particular object, method, or property, highlight the object, method, or property in the VBA IDE and press F1.