Lower your eyes if it's comfortable to do so and bring your focus to your breath.
Picture a square in front of you and start in one corner,
Any corner,
It doesn't matter which one.
As you breathe in,
Travel along in your mind's eye one side of the square.
As you breathe out,
Travel along the next side of the square.
As you breathe in,
Continue along the sides of the square and breathing out,
Back along the final side to complete the square.
Repeat this for as long as you wish,
Just breathing in and breathing out as you move along the sides of your square.
When you are ready,
You can let go the attention from your breath and the square and slowly open your eyes.