You have to just come for the Puja. 

For Seemantonnayanam please include three or five or seven Soubhagyavati ladies in your guests.

For annaprashan please bring the item to be fed along with utensils(cup, spoon, plate etc) 

For Chudakaran please bring a towel and one set of clothes for the baby and father. Amount to be paid to the Barber directly at the venue. 

For Engagement please bring rings.