*Important note: The mixture should be large enough for the batch of concrete you want to make. Mine was a little too small and I paid for it with poor mixing. I ended up adding more water and water reducing admixture to get things mixed.
The concrete was placed into the forms by hand being sure to press the first layer in well. That prevents air pockets on what will be the surface. A pad sander without sandpaper works well to vibrate the sides.
Since the concrete did not get mixed well, we had to pick out the clumps. Although you can not see them in the final piece, poor mixing lowers the strength and makes cracking more likely.
Then everything got wrapped in plastic and hung out for one day. The longer the concrete stays in the mold, the stronger it will be. One to four days is typical to let it cure before taking off the forms and starting the finishing process.