The first thing to know about the system is that there are 3 modes you can operate in: edit, arrange and preview. Edit mode (Figure 1) enables you to edit modules that are on the page and insert new ones. Arrange mode (Figure 2) enables you to move around the modules that are currently on the page. Preview mode (Figure 3) enables you to preview the page and see how it looks in a web browser without the editing features showing. 

If you notice that your editing bars have disappeared, make sure you are in the correct mode. More than likely, you inadvertently switched to preview or arrange mode without realizing it. Switch back to edit mode and you can begin editing your pages again. The screenshots below will highlight what the different modes look like. 

Figure 1 - Edit Mode

Figure 2 - Arrange Mode

Figure 3 - Preview Mode