Sanskrit
शुचौ देशे प्रतिष्ठाप्य स्थिरमासनमात्मनः । नात्युच्छ्रितं नातिनीचं चैलाजिनकुशोत्तरम् ॥
śucau deśe pratiṣṭhāpya sthiram āsanam ātmanaḥ nātyucchritaṃ nātinīcaṃ cailājinakuśottaram
Translation
In a pure place, established on a fixed seat of his own, neither very much raised nor very low, made of a cloth, a black antelope skin, and kusha grass, one over the other;
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
The instructions turn concrete: a clean, quiet spot, a stable seat, neither too high nor too low, layered cloth over antelope skin over kusha grass. The source print edition had a typo here (chelājina for chailājina), corrected in this text — a proofing fix, not a textual variant, though it does change the transliteration’s initial vowel.