This person is taking their time to carefully color in a mandala design. They have chosen a beautiful blue pen to bring out the intricate patterns within the mandala. Every shade and hue of blue will give each pattern a unique and vibrant look as they fill out each section and create an eye-catching piece of art. To bring out the colors even more, I suggest that this person use various shades and tones of blue, along with a white or light gray highlight. Taking the colors slowly, with light and dark blues, can bring out the different designs and create an even more captivating finished product.