Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 7 · Samskara Muhurtas
संस्कारमुहूर्ताः
अरिक्तापर्वदिवसे कुजजीवार्कवासरे ।तीक्ष्णमिश्रार्कवर्ज्येषु पुंभांशे रात्रिनायके ॥ ३२२ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 322.
Choose a day that is not rikta (empty tithi) or a parva (junction day). Use Tuesday, Thursday or Sunday. Leave out the sharp and mixed stars. The Moon should be in a male navamsha (one-ninth part of a sign).
Simple meaning: Pick a day with no empty or junction tithi, on Tuesday, Thursday or Sunday, with the Moon in a male navamsha.
शुद्धेऽष्टमे जन्मलग्नात्तयोर्लग्ने न नैधने ।
Keep the 8th house clean, avoid the 8th from either parent's birth lagna, and let good planets support the rising sign.
शुभग्रहेषु धीधर्मकेंद्रेष्वरिभवे त्रिषु ।
Good planets in the 5th, 9th and corners, bad ones in the 3rd, 6th, 11th, and the Moon in a good house.
क्रूरग्रहाणामेकोपि लग्नादंत्यात्मजाष्टगः ।
A strong cruel planet in the 12th, 5th or 8th house can harm the mother or the child.