Srimad Bhagavatam — Ekadasha Skandha, Shloka 19
शुचि: सम्भृतसम्भार: प्राग्दर्भै: कल्पितासन: । आसीन: प्रागुदग् वार्चेदर्चायां त्वथ सम्मुख: ॥ १९ ॥
śuciḥ sambhṛta-sambhāraḥ prāg-darbhaiḥ kalpitāsanaḥ āsīnaḥ prāg udag vārced arcāyāṁ tv atha sammukhaḥ
净身并备齐供具后，礼拜者应以库沙草铺设座位，使草尖朝东。随后面向东或北而坐行供奉；若圣像安置固定，则应正对圣像而坐。
The word sambhṛta-sambhāra means that before beginning the Deity worship one should place all necessary paraphernalia nearby. In this way one will not have to get up continually to search for different items. If the Deity has been permanently installed, then one should sit facing the Deity.
FAQs
This verse teaches that one should be clean, collect the needed items, prepare a proper seat (traditionally with darbha grass), and only then begin worship of the Deity.
Krishna is outlining an orderly arcana-vidhi: sitting in an auspicious orientation (east or north) and worshiping while directly facing the Deity, emphasizing attentiveness and proper ritual focus.
Keep yourself and the worship space clean, gather your items before starting, sit in a steady place (a simple mat works), face east or north if possible, and worship with full attention facing the Deity.