Breathing is a valuable meditation tool in itself. Simply focusing on the breathing can relax and ease anxiety. Assume a comfortable position, either sitting or lying down. Relax your body slightly. Inhale through your nose to a slow count of 1, 2, 3 - Hold the air, then exhale to the same slow count, backwards.
Repeat this several times, gradually slowing your breath rate. Never hold your breath past the level of comfort. The inhalation, retaining & exhalation should be controlled, calm, free of tension. Concentrate on your breathing process while doing this. As you inhale - breathe in love, health, tranquillity, visualizing these positive energies as sparkles in the air.
Exhaling, breathe out fear, anxiety, anger, all negative emotions - visualize it as dark smoke exiting from your body.
Practice deep breathing exercises daily & gradually increase your capability to retain air. This will also help you stay balanced and focused throughout the day, and you can do this meditation anywhere - driving, at your desk, while you do the dishes, etc.