Sit cross legged and imagine a pole is between your legs, similar to this image. Make it a reflective, metal pole. Now in your mind’s eye, see yourself holding the pole with both astral hands (your physical hands remain on your thighs), your nose touching the pole, and seeing your eyes/forehead in the reflection of the metal pole. This trains the visual and feeling senses simultaneously. As hearing is also important, you can imagine the pole reaches up to heaven, is constantly hit on a higher plane and the sound of frequencies reverberate down the pole, constantly giving off a hum. You can also imagine putting your tongue on the pole to taste it since your nose is touching it. Hold this as long as you can. It forces your senses and attention to be centralized & unified.

Start with one action at a time to harness then add another, like first hold the pole, then put your nose on the pole, then see your reflection, then put your tongue on the pole, then hear/feel the vibration of sound coming down the pole. To add more flair, imagine you are doing this in an inspiring landscape, such as in a temple or on a beach.