Dirty Mindfulness:

For whatever reason, we tend to rely on sight more heavily than our other senses. But bringing attention to touch, taste, texture, and sound, can really allow one to focus on the moment.
 
To do this sound-based exercise, find a place outdoors where you like to sit, be it in the setting of a city park, on the bank of a river, or in the woods. Get comfortable and become aware of your body in the environment. Feel what supports your weight; it might be the ground, a log, or bench. Notice what sensations you encounter as you take a few deep breaths. 

Begin by drawing your attention to whatever sound is farthest from your body. It might be the rumbling of a distant train, a bird chirping, or whatever the environment provides. Is the sound static, does it grow or diminish in intensity? Pay attention to its quality.

When it feels right, shift your attention to a sound a bit nearer to you, and bring your alertness there. Try to focus on that sound. You needn't attempt to shut other sounds out, just bring your attention to this mid-distance sound.

When it feels right, bring your attention to the sound closest to you. It might be the wind in your ear, or the ripple of the water as it hits the bank. Let your awareness rest there for however long feels comfortable.

Finally, bring your awareness to your own breath, the subtle, almost internal sound of nourishing breath entering and exiting your body.

For more mindfulness exercises, check here.