When I add a component, how is it added to my toolbar?

When you add a component, it blinks and is highlighted on your toolbar so that you can easily see the new addition. It is added to the first position in the My Stuff area to right of the Add Stuff button. After you have added several components (depending on their size) to the My Stuff area, any new components will go into a chevron menu and don't take up any more room.