A weight of ~1.0 is recommended (You might want to adjust the weight depending on your model). Feel free to experiment with other weights and share your results if you want to!
The main prompt is "Ceres Fauna". You probably always want to use "antlers" aswell.
Use "long hair, braided bangs" for her hair and add "hair flowers" for her flowers.
For her outfits you can try the following prompt: Base: "FaunaBase, long hair, braided bangs, hair flower, blue dress, wide sleeves, single thighhigh, bridal gauntlets"
Casual: "FaunaCasual, long hair, two side up, white shirt, black skirt, cardigan, open cardigan, cleavage cutout, black choker, ribbon, jirai kei" You might want to add "see-through, pantyhose" to negatives. No clue why it wants to draw her with a pantyhose.
New Year's: "FaunaKimono, long hair, twin braids, hair ornament, pink kimono, floral print, bow, apron, sash"
Bonus Cowkini: "Ceres Fauna, antlers, print bikini, cow print"
Let me know if you have any issues.