Drawing Gum is a peelable solution used to keep areas of artwork free, for use with ink, watercolour, diluted gouache, ... It is used on paper, cardboard, Bristol board, acetate, wood, ... using a brush or pen on parts of the work to be masked. Apply colour when the drawing gum is dry. Once the colours are completely dry just rub the gum with your finger or with an eraser to reveal the masked parts.