Step 2: Playing with Finishes
Possibly the best bit, of any concrete project, is playing around with the finishes.
This is your chance to metaphorically slap anyone who has ever said:
"Concrete? Isn't that a bit dull?"
Most of this was relief work (putting stuff inside the moulds to create patterns in the surface of the concrete).
You can also add dyes to the mix or stain the concrete afterward.
Build yourself some small wooden boxes and try as many different materials as you can get your hands on.
Among my favourites are the glue gun patterns and the leaves, the mixture of organic and man made, plus it kind of looks fossilized.
We also experimented with using glass as an aggregate, but this requires lots of grinding / polishing to see the bits of glass.