First, an aside. I was already an Asatruar when I found kundalini meditation, so my meditation practice has been guided by The Way. I already knew that the Brahmins of India were close kin of our European ancestors (thus, the Indo-Europeans), so I find no contradiction between Asatru and meditation. In fact, the two enhance and complement each other.
Practicing mantra during meditation helps occupy the "squirrel mind," allowing it to be helpful rather than distractive. The mantras that I use are sometimes from my yoga instruction but more often constructed of our own legacy - runework.
For example, the most well-known yogic syllable is "OM." Properly written, it is spelled AUM. Looking to Thorrson and Cleary for rune meanings, we find that (in this context) Ansuz means "creative wisdom, ecstasy, inspiration, transformation;" Uruz means "Induction of magnetic and subtle energies, formative force;" and Mannaz means "enlightened man, divine ancestor, the link between man and the gods." Thus, AUM is seen to be the creative wisdom inducing subtle energy to link man to the gods. More than mere coincidence, it seems to me.
Similarly, one can use the cauldron work laid out in Mr. McNallen's book - Bothn, Son, and Odrereir. The three cauldrons have parallels not only in the primary chakras or energy centers of kundalini but also in Taoist alchemy where these centers are also called cauldrons. Thus, one can chant the name of each cauldron in succession, or the individual runes, as energy is raised from the pelvic floor and lower chakras (Bothn) to the heart (Son) and then to the third eye point (Odrereir).
Also, one may galdr the entire Futhark (I call it "making the world"; long explanation), or some other runic bindrune carefully chosen after long study and contemplation. The basic idea of any mantra work remains the same whichever technique one chooses.
So: take your place in front of your altar, or any other quiet place where you can remain undisturbed for fifteen minutes. I typically sit in the Adept Pose with my hands in Gyan mudra.
When I am a bit more flexible, I sit in the half-lotus with my hands in the Buddha mudra. Either way: sit, settle, relax; head tilted down slightly, eyes closed and rolled up as if looking out between the eyebrows.
Inhale from the diaphragm; imagine the breath as a source of energy from Ginnungagap, down the front of the body into the pelvic floor. Pause the breath, then exhale and allow the energy to travel up the spine to the higher centers. With the exhale, galdr the mantra you have chosen. Be relaxed, but diligent. AAAAAUUUUUUUMMMMM........
You can galdr or mantra a combination of runework also: three breaths of ALU (to invoke and manifest holiness and sacrality), three breaths of AUM, then three breaths of the Futhark.
This work is made to raise the kundalini energy (or Ond, or Chi) from the base level to the higher centers: envision the base appetites transformed into love of Folk and Rational Judgment. Change does not come overnight but over years. I am as impatient as anyone, but I know this work has improved my life. Discipline, perseverance; 15 minutes a day, or an hour..........
Lawspeaker Allen Turnage