Bokeh is the Japanese originated concept of the difference between out of focus areas of an image due to lens design..  The word comes from Japanese language, which literally translates as “blur”. A simple explanation is, the quality of out of focus blur..  Producing nice bokeh involves creating a shallow depth of field..  The blur that you are so used to seeing in photography that separates a subject from the background is the result of shallow “depth of field” and is generally simply called “background blur”. The quality and feel of the background / foreground blur and reflected points of light, however, is what photographers call Bokeh. .

Prime lens create exceptionally good-looking bokeh, but my kitlens 18-55mm surprisingly  capable of producing pictures with beautiful bokeh too.. of coz you have to play with the setting and zooming.

Remember, bokeh is rendered by the lens, not the camera.  Another popular technique is to create different shaped bokeh. You can make stars or hearts shape  like the image below.

Cut and shape the sheet to make a fake lens hood. The Diameter is made so that it snugly fits on the lens.  In the middle of the filter the wanted bokeh shape is cut out - in out example a heart is used. I’m not sure how big a hole the shape can be. But you can check it right away by just looking through the viewfinder..  Dont forget to set your camera to its lowest aperture value (completely open).