1.The root chakra has four petals and is often visualized as parallel to the ground.
vaṁ, śaṁ, ṣaṁ, saṁ
2.The Svadhisthana (2nd chakra) has 6 petals.
baṁ, bhaṁ, maṁ, yaṁ, raṁ, laṁ
3.Then the petals of the navel chakra are visualized with the next 10 letters.
ḍaṁ, ḍhaṁ, ṇaṁ, taṁ, thaṁ, daṁ, dhaṁ, naṁ, paṁ, phaṁ
4.heart chakra is visualized with the first twelve consonants of the Sanskrit alphabet.
kaṁ, khaṁ, gaṁ, ghaṁ, ṅaṁ, caṁ, chaṁ, jaṁ, jhaṁ, ñaṁ, ṭaṁ, ṭhaṁ
5.throat chakra is visualised
aṁ, āṁ, iṁ, īṁ, uṁ, ūṁ, ṛṁ ṝṁ ḷṁ ḹṁ eṁ aiṁ oṁ auṁ aṁ aḥ
6.ajna chakra
Hum and shum