Okay so, when you are installing vBulletin 4, there is an option to install the default CMS data, if you select "no", you're left with an empty CMS which you have to lay out and fill up! This guide will serve as a reference on how to get started. Some people will be baffled as to where to start, but after reading this, you'll not want to stop
First, you need to create your widgets for your futures pages. You can do that on AdminCP > vBulletin CMS > Widgets. Click "Create New Widget", select your options and save.
Do this for each widget you want to create.
After saving each widget, you can configure them by clicking on "Configure" right or each widget.
Second, you need to create grids. Go to AdminCP > vBulletin CMS > Grid Manager. Click "Add New Grid", select your options and save.
After the grid is saved, you can "flat" the grid. These will not allow to edit anymore your previous options (they are saved and used anyway) but you can edit the Layout Manager UI HTML and Default Template HTML.
Third, you need to gather all widgets and grids into layouts. Go to AdminCP > vBulletin CMS > Layout Manager. Click "Add new Layout", enter a title and select a grid. In the same page, the grid will be howed to you. Select a widget on the left, click ">" and it puts the selected widget on the first showed column. You can move it with drag & drop to the column you want to use.
Do this for each widget / grid / layout you want to create.
Finally, you need to display that in the front-end.
Go to your home page (or the wanted section if this is for a section) and click on the pencil you can show on the right of the page name (it appears when the cursor is in the same line as the page name).
In the next page, select the layout you want to use, and click "Save" in the top-right corner of the page.
Do this for each section you created in AdminCP > vBulletin CMS > Section Manager
Edit by Mikey - Copied this post from this thread to make this basic how-to and stickied it.