Bokeh is what we used to call the out of focus crap in the background. Now a compositional element/technique. If used well, bokeh can enhance some images.
Look for elements in the background that will make aesthetically pleasing patterns when thrown out of focus.
- Small lights, small Christmas lights work well.
- Variations in illumination.
Here creamy bokeh produced by sunlight on fern fronds provides a contrasting background to the fiddlehead.
The bokeh here provides a subtle background to the fall coloured leaves in the foreground.