This is a picture of Easy Pose. The woman is meditating with her hands in the traditional yoga (Jnana) Mudra--palms up, forefinger and thumb touching. If you can do a Full- or even Half-Lotus, all the better. If all you can do is sit in a chair, that will suffice.
Sitting comfortably, turn the palms down rather than up with the middle/ring/little finger pointing downward. Root through your fingers and your sit bones. The emphasis is on feeling grounded.
The seed sound for muladhara is LAM and you can hear it at this website. Repeat this seed sound, extending the consonants as you feel led or simply hum on the same key (C).
I hold a mala necklace and count off the number of repetitions as I chant. You may choose to do something similar or just chant for however long you like.
Close the meditation by raising your hands in the prayer mudra (Anjali).