In the “Home Page Before Content” Widget Area a “Text” widget was used. Leave the Title field blank:
Home Page Before Content Widget Area

Home Page Before Content (Click here to grab the code behind this layout)

For the rest of page examples, below are the corresponding content area source code used with a “Text” widget:
Bottom Area Widgets

Home Page 1 Example (Click here to grab the code behind this layout)

Home Page 2 Example (Click here to grab the code behind this layout)

Home Page 3 Example (Click here to grab the code behind this layout)

Home Page 4 Example (Click here to grab the code behind this layout)

Home Page 5 Example (Click here to grab the code behind this layout)

Home Page 6 Example (Click here to grab the code behind this layout)

Home Page 7 Example (Click here to grab the code behind this layout)

The shortcode based column layout described above is only one way of implementing columns on the home page. Feel free to experiment with all Home page widget areas, for example you can use Widget areas alone to create one, two, three or four column layouts.

The following describes how I’ve setup the Bottom Area Widgets (the four columns):
Bottom Area Widgets

Bottom Area Widgets (Click here to grab the code behind this layout)

Other Resources:
32x32 Icons Used in the Demo