It is traditional when concluding a pranayama session to do 11 Om chants followed by 3 Om shanti, shanti, shanti chants. However, this is purely your choice. If you do not want to chant you can simply sit quietly for a few minutes.
Either way, before opening your eyes rub your palms together and place them over your eyes. Massage your eyes, temples, forehead, and underneath the cheekbones. Keeping the hands over the eyes, gently open the eyes and bring the hands down and place them on your legs, palms down.
If you wish, you can bring your hands together in a prayer position, raise them to your forehead, and gently bow.