Sloyd objects are pre-set with materials. Objects are made out of shapes and each shape is assigned one of four materials. This group of materials are called a palette. This makes it especially easy to texture Sloyd objects with your own textures and even as the object is edited, changes dimensions and have sub parts added to it, it remains textured.
More on Sloyds Material Palette setup here:
Material Palettes (https://doc.clickup.com/d/h/kh4k0-705/ed114594b2af381/kh4k0-7615)
Under the Sloyd Object Container, look for a the 'Sloyd Palette' section. There you'll see four material slots. Drag and drop materials to each slot, or select from the material menu. The materials you add will be applied to parts of the object automatically.
If a material has been updated and you want the update to be reflected on the object, press 'refresh materials'.
You can assign material palette to each object individually, as explained above. Or you can create a SloydPaletteApplier object and drag SloydObjectContainer into them. In that case, when the SloydPaletteApplier is updated it will retexture / reapply materials to all the objects that were assigned in inspector.