In past experiments, I applied color through tea or during the fermentation process.
I had a dry sheet of pellicle that I wanted to apply dye with a pattern so I submerged a dry sheet to make it more malleable and put some rubbers band to create a sort of dye experiment.
It is partially dye so now but perhaps I could build up of some color. After it drys I hope to see the vibrant and start experimenting with