The internal clearance pranayama taught by Shri Vethathiri Maharishi is a wonderful practice that can be done before meditation.
The mind is in an active wakeful state during the day as long as it is attached to our senses operating at the beta level of frequency above 14 cycles per second.
For the mind to move to alpha level of frequency it is important to disconnect the senses.
This is done by practicing the clearance pranayama technique.
Here is a demonstration of how the pranayama can be done.
It is a gentle and beautiful experience.
As you inhale you have to imagine the life force raising from the mooladhara to the agna chakra through the spine.
As you exhale, let the life force move down from agna to mooladhara chakra.