तस्मिन्यावत्संपातमुषित्वाथैतमेवाध्वानं पुनर्निवर्तन्ते यथेतमाकाशमाकाशाद्वायुं वायुर्भूत्वा धूमो भवति धूमो भूत्वाभ्रं भवति ॥ ५ ॥
In plain words
Having lived there until their accumulated merit is exhausted, they return by the very path they took to ascend: first to space. From space they pass to the wind; becoming wind, they turn into smoke; and becoming smoke, they turn into a cloud.
Close to the Sanskrit
Having dwelt there until the exhaustion of their merit, then they return along this very path by which they came—to space. From space to wind; having become wind, it becomes smoke; having become smoke, it becomes a cloud.