Thank you Cris for this helpful class! I was going to attend a risography workshop, and having never tried riso before, this helped me a lot to prep for printing!

I combined this class with Weronika Salach's Isometric Illustration in Procreate: Design Your Dream Room. The workshop was to make A3-sized prints in 3 colour inks, so I designed this picture specifically for that. I wanted to explore the colour-mixing combinations using something very colourful, and then I thought that an art-supply shop was the ideal background for that ^_^

The A3 riso print in fluorescent pink, yellow and medium blue (available in my webshop!)

Process

I first made some colour swatches to decide whether I wanted fluo pink+yellow+medium blue (left) or fluo orange+yellow+medium blue (right). Of course, you can get many more colours from these inks, by varying opacity and adding triadic colours, but I just needed a quick guide. I decided to go with the first combo in the end because I liked the purples better:

I sketched the image (more details on that in my project from the isometric class), then brought the inked outline into a new Procreate file, setting up the colour layers using the clipping mask+multiply method:

To colour, I started with a background color with light grey on the "yellow" layer and very light grey on the pink layer. I did not know how to be accurate in terms of ink percentage, so I picked a color palette of a dozen different values of grey beforehand to use for ink intensities. For the walls, I used slightly darker grey on the pink layer and lighter on the yellow layer. For the green on plants, I painted over the leaves in white on the pink layer, then added medium grey on both yellow and blue layer, with variations to create shadows.

The grayscale layer for blue, plus the lineart on a different layer (later I turned it black and merged it down to the "blue" layer for the printer)

The riso studio hosting the workshop (Quintal Editions) has double-drum riso printers, so they could test print both pink and yellow at the same time:

Test print in blue:

Details (aaah the texture!):

The digital illustration done in Procreate:

Thank you for reading! ^_^ If you like my work, you can find me on Instagram @echo.ism and @echo.printmaker.