Not only do a few drips add dimension, but they also provide a point in the design that the eye is instantly drawn to.
To create a drip in your work, saturate a round paintbrush with water. Place the brush into your paint. Place the loaded paintbrush on the edge of your work and press down slightly until a bubble of paint appears. With your brush in place, tip the work up slightly, allowing the drip to move down the work. Place the work flat once the drip has reached the length you prefer. Repeat as desired.