I could not find much on rituals for giving yourself a magical name. However, I feel confident that I can write my own, for the Kemetic and Druid pathways.
For my Druid Name:
Ancestors, Nature Spirits and Shining Ones,
I present myself before you as a grown woman
living the course of her life.
I ask you to hear me out,
that you might recognize me by a name I have chosen,
Siofra, meaning “Elf” or “Fairy”.
This is the name I chose for you to know me by.
I give you this humble offering as Siofra. (incense)
Ancestors, Nature Spirits, and Shining Ones,
Please recognize me now as my new name,
which I will use to worship you.
So be it!
My Kemetic name:
I speak to you, my Gods, and ask for you to hear my words.
Ra of the Sun, Isis of many names, the child Horus and the God of the Underworld, Osiris,
And the many Gods I did not name here, I speak to you also,
and offer my praise.
Take this incense, may it show my purity and devotion
May the smoke carry to you my praises
I ask that you recognize me as Nathifa
May you be blessed, as you bless others.
At your shrine I am Nathifa.