Let me start with the first group as example:
Grieva
Name - position - colour
Kyouki - Vocals - yellow
Haru - Guitar - red
Roku - Guitar - black (1/2) purple (1/2)
Hisame- Bassist - blue
yuugo - Drums - grey
(Rui - Drums - black)
(Note)
roku changes his trademark colour from Purple to Black with Rui‘s department.