Today I started inking in.
I'm using Posca pens.
They're semi-permanent. You can wipe over them without erasing the lines but if you scrub at them, or use window cleaner, they come off quite easily. I like that my artwork is temporary. I find it frees me up to not worry so much about making mistakes which, paradoxically, means that I make fewer.
...but still one of my main thoughts is, "Where's the CTRL+Z for live drawing."
My artwork is temporary - only around until 20th March.
I'll be at the Wellcome Collection drawing live today.