Shiva Purana
अथ यस्यास्त्यवसरो नास्ति वा मतिविभ्रमः ॥ स विस्तीर्णेन कल्पेन न्यासकर्म समाचरेत् ॥ २१ ॥
He who has sufficient leisure and is not confused in mind shall perform the rite of Nyāsa in a detailed manner.
english translation
atha yasyAstyavasaro nAsti vA mativibhramaH ॥ sa vistIrNena kalpena nyAsakarma samAcaret ॥ 21 ॥
hk transliteration by Sanscript