To create a Twi'lek character, simply specify whether you want a "male Twi'lek" or a "female Twi'lek".
Adding a specific style like LoRA can enhance the result. The training data mainly consists of images from SWTOR and KOTOR, giving it the appearance of an old 3D video game.
Since there are more and better pictures of female Twi'leks, generating a female character will likely yield better results than a male character.
If you have a preference for a specific skin color, use the format "[color] skin". For example, "Green skin" or "blue skin".