It has been a long time since I painted a proper anime background by hand, so I did one for practice from a random Tumblr photo. This time I used acrylic gouache (by a company called Turner) instead of the usual poster colours.
I find the gauche a lot easier to use. When dried, they become waterproof so even if I paint over something the colours don’t bleed at all. I have a set of 24 standard colours and bought some bonus ones - there are more than 200 hues from the Turner brand!