Slow shutter speeds and long exposures enable you to create motion blur in your photos. Again, the speed of the moving object will determine how slow the shutter speed needs to be.
A shutter speed of 1/30 sec works well for bicycles, whereas shutter speeds between 1/60 sec and 1/125 sec work well for cars and motorcycles. If you want to blur a waterfall, a relatively long exposure of 3-5 seconds is best. This also works well for 'blurring' people out of shots when they're walking around, effectively removing them from architectural shots of street scenes or busy landmarks.
In bright daylight, it can be difficult to achieve a shutter speed long enough to create motion blur, even if you're using a narrow aperture. To overcome this you can place an ND (Neutral Density) filter in front of the lens to reduce the amount of light hitting the sensor, allowing you to extend the exposure. In some instances, your exposure might go beyond 30 seconds. In which case select the camera's manual mode and use the Bulb setting.