步斗踏罡

bù dǒu tà gāng

to worship the astral deities (idiom, refers to Daoist astrology)

a step

dǒu

abbr. for the Big Dipper constellation 北斗星[Bei3 dou3 xing1]

to tread

gāng

stars of the Big Dipper that constitute the tail of the dipper