There are 3 modes that the website can operate in after you login with your Admin Account. Those 3 modes are:
You can switch between these modes at any time using the "Mode" dropdown in the upper right of the site when you're logged in.
The View Mode simply shows you a preview of exactly what the site will look like to a logged-out user. It simply saves you the hassle of logging out to see what the page will look like to all other users. If you ever find your website to be void of the editing controls you're used to seeing, check to make sure you're not in View Mode first.
The Edit Mode essentialy turns on all the editing controls on the website. You'll see all your "Manage Buttons" as well as other functionality that allows you to edit the website. This is the mode you will be in 90% of the time as an Administrator of your own site.
Your website's Layout Mode has one purpose, to help you rearrange the content on your page. If you go into Layout Mode, you'll notice your website will appear much different than the other modes. All you'll see is the headers for any modules on your page, and it will show you a bunch of titled boxes as to where modules can be placed.
Please pay special attention to the names of the "Panes" in this image. You can place or move modules (textboxes or any functionality on your site) to any "Pane" shown above. This allows the website to be VERY flexible when it comes to layout:
The ContentPane is the default pane and will be used the most often. If you want to do a 2-Column layout on your page, you can simply put one HTML Textbox in the Content Pane and one in "SidePane2". If you'd like a 3-Column Layout, you can put HTML Textboxes in "SidePane1", "ContentPane", and "SidePane2" to achieve this.
To move an item from Pane to Pane, simply mouseover the "Manage" button of the module you'd like to move, and select which pane you'd like to move it to in the bottom portion of the popup menu: