7 Add masking agent

I’d like to achieve an old and rusty look, so I am applying masking agent with the wrinkled plastic bag to get the kind of texture that cannot be painted with the brush. Masking agent needs a few minutes to dry. Those speckles of dried agent will protect the paper from colour. I am painting a thin layer of acrylic colour over the entire frame. Those areas will be darker, and masked areas will be lighter.