DOING IT: 

Using a compass, first determine the precise direction of north/south. Now align your body along north/south lines by laying down with your head toward the south with feet pointing north.  Begin to relax your mind and your body by watching your breathing.  

Next, envision your body dissolving into whatever you are laying on.  Of course, you are not expected to really believe this, but just try to imagine the sensation. Continue this visualization with whatever is below that, and then below that, until you begin to feel yourself merging with the ground.  Actually try to feel as if you are "one with" and part of the ground and eventually the Earth itself.  Guide your mind to think about the enormity of the planet Earth.  Picture it spinning on its axis, strategically suspended in space and envision what it feels like for your body to spin with it.  Deepen this visualization until you can actually feel yourself spinning with the Earth.

Next, focus on the lower half of your body which is facing north.  Imagine yourself like the magnetized end of a compass needle perfectly aligned with the Earth's magnetic field.  Remaining for now with just the lower chakras (ending with the heart one), visualize energy moving through your chakras as if doing the color-chakra exercise.  

At the end of five minutes, you want to reverse the position of your body so your head points north and your feet toward the south. Follow the same procedure outlined above, but this time begin the visualization with energizing the upper part of your body starting with the heart chakra and concluding with the crown chakra. 

Be sure you continue this for at least five minutes in each direction. Of course, as with other meditation exercises, do them for a longer period of time, if at all possible.