How to use depth of field on a Nikon d5000?

I'm confused on how to exactly make this happen. If I make the depth of field smaller does that make the background less blurry or do you want the depth of field larger?

Http://en.wikipedia.org/wiki/Depth_of_field

Learn what depth of field means.

How to use it: DOF is controlled by aperture. The smaller the f/ the smaller depth of field or depth of focus. The larger the f/ the larger the depth of field. To get a shallow DOF you want to use an f/1.8 or faster lens. To get a very large area of focus you may need to use f/11 or even f/22 depending.
DOF is also affected by how close you are to the subject either by physical distance or zoom. The closer you are to something the shorter the depth will be.