This exercise was frustrating but didactically very rewarding, I learned the hard way that one needs to spread the color with the water brush very quickly, before the applied paint dries. The background layer is a mess :)

I used 100% cellulose paper (cotton would likely have been a better choice) and my Faber Castell watercolour marker set (very intense pigmentation!) didn‘t have any light grey or yellow ochre so I had to mix colours or use dark values and tried to spread with water as much as possible. 

 

Thank you Elisabetta so much for teaching us!