Paper and color (crayons and chalk work especially well for rubbings) are
all you need to get started. Next find some handy items with
interesting texture. Place the paper over the textured item (the bark
of a tree, for example) and rub your crayon or chalk over the paper.
The texture of the item underneath the paper will create an interesting
design.
Here is an idea for using different textures and different colors to
create landscape pictures.
A Lifetime of Color - Texture Rubbing Landscapes
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