First up, some preliminaries on drawing paper. The top is simply graphite, but this time with some smearing. The bottom is an acrylic wash. The acrylic works just like watercolor, but subsequent washes don't mix with what's underneath. Once it dries, the color is fixed.
The smearing above was an interesting experience, so I gave it a try on a larger scale. This one's on smooth bristol (big mistake). The smooth texture won't take much graphite, so getting those dark values is a challenge.
Longing for more texture, this one's on some pretty hefty watercolor paper. I did an undercoat of sepia acrylic, and then overcoats of watercolor washes for the colored items. Then graphite over the whole thing for tone. I like kind of like this one.