Haṭha Pradīpikā Chapter Two verse 1

अथासने दृधे योगी वशी हितमिताशनः ।
गुरूपदिष्टमार्गेण प्राणायामान् समभ्यसेत् ॥१॥

athāsane dṛdhe yogī vaśī hita mitā aśanaḥ |
guru upadiṣṭa mārgeṇa prāṇāyāmān samabhyaset ||1||

atha - now, 'now' (begins); an auspicious and inceptive particle; A particle used at the beginning (of works) mostly as a sign of auspiciousnessāsana - particular posture; sitting, sitting down; seat, place, stool; abiding, dwellingdṛḍha - firm; solidyogin - a follower of the yoga systemmārga - seeking, search; way to or through; road, path, pathway; the track of a wild animalprāṇāyāma - extending the breathabhyāsa - practice; the effort of the mind to remain in its unmodified condition of purity ; repeated or permanent exercise, discipline, use, habit, custom;āroḍhum - to ascend