It can be a bit confusing at first and you have to take your time in making each evolution unit carefully (The ones you see in the pic provided by Eversor) so you don't accidentally waste yazou's.
And as Eversor also said you level up yazou with other yazou's to increase her luck value and you Evolve/Godify with the right star and luck valued unit to increase her star value as per the picture.
This event is over now so until they bring the next unit our way you wont be able to do much with her any more unless you have some fodder of her saved up.
On another note looks like the daily login reward changed to magas and not oda... was looking forward to another oda copy
Is anyone else doing the Idol Wars Z cross over event?