Here is a neat YouTube video that will show you how easy it is to achieve beautiful and realistic cloth effects in Blender. If you are confident that you know the basics of Blender then you can skip the first two minutes of this 17 minute video.

The basic idea of making the cloth fold like this is to make a rectangle of cloth, move it above the glass bowl and then let it fall. Blender knows about gravity and will make the cloth fall in a physically accurate way, colliding with the bowl and the floor, and then you just have to choose the nicest frame of the resulting animation.

Click HERE to view the video in YouTube.