How do I pick up a blurred environment near the canon eos 1000d?

I'm a complete beginner to digital slr photography, and have trouble obtain a blurred background to images? i seem to be to be able to get the blurred effect when I don't try, and when I certainly want it can never get it right.I think I call for to do a small photography course.

But until then..If somebody could tell me the correct settings to enjoy on the camera, as well as if a particular lens is best to use, it would be really much appreciated!!

thanks