Ok I am new at this so if it doesint work plz dont get mad at me. :)
Things you shall need:
Sea shell {any size}
Has to ba a full moon
2 blue candles {representing water}
2 candles (of what you want your tail color to be)
Water
sea salt
holy water
Step 1: Light the candles
Step 2: Put some part of your body in water.
Step 3: Put the holy water in the shell.
Step 4: Cover your legs in the sea salt.
Step 5: pore the holy water on your legs and say " God here my plea,make my wish come true oh please,make me a creature of the deep, a mermaid"
Chant 4 times.
Step 6: Go outside under the full moon and chant the spell a fith time.
Step 7: go to bed with a shell (or something from the sea) next to you.
