Unfinished Artist Panel (Maple, Birch, or similar)
These products are typically found in art supply stores and are generally a good option; kiln dried, relatively stable, and engineered for this purpose.
Acrylics, Oils, Watercolors & Drawing: You can draw or paint directly on wood panel. When painting with any acrylic paint, medium, or ground, 2 or more coats of Gloss Medium can be used to reduce the potential for support induced discoloration. Acrylic gel or paste can be applied to alter the surface’s absorbency, and durability for painting. Grounds or textured gels and pastes can be applied to make the surface more receptive and consistent for drawing with dry media such as pastels, graphite or charcoal.
Video: Support Induced Discoloration (SID)
Article: Understanding Wooden Art Supports: A brief history
Tech Page: Support (surface) Preparation
Hi, as I paint mainly Still Life I find that braced ply or Birch panels are my go-to substrate. I need a flat firm surface to enable me to paint details of the various objects etc. Two or three coats of gesso sanded between coats give me a really great surface on which to paint. Ne ver had any problems at all with this substrate.