Yoga Rahasya Chapter Two verse 45

sthiti-krama-anurodhena gṛhiṇām yoga-sādhane |
prāṇāyāmo mukhyatama iti me matam-uttamam ||

In the Sthiti Krama the most important Yoga Sādhana
for the householder, according to my view, is Prāṇāyāma.

sthiti - staying or remaining or being in any state or condition; continuance in being, maintenance of life, continued existencekrama - a step; progressing step by step, a particular manner or method of reading and writing Vedic texts; sequence; order; series; regular arrangement; succession; in regular course; gradually, by degreesgṛhastha - standing in the home; living or staying in any one's house; householder; a life stageyoga - the act of yoking, joining, attaching, harnessing; a yoke, team, vehicle, conveyance; employment, use, application, performance; a means, expedient, device, way, manner, methodsādhana - means to accomplish; leading straight to a goal; guiding well; furthering; propitiation, worship, adorationprāṇāyāma - extending the breathiti - thus; in this manner; something that has been said or thought; having so saidmata - a thought, idea, opinion, view, sentimentuttama - most elevated, principal; uppermost, highest, chief; best, excellent