Covering the mesh with greebles
Once you’re happy with how the insert responds to your cursor you can undo it, giving a blank base. Press Space again and this time, from the Target menu, choose All Polygons, then draw out like before, this time with a cube on each face.
The Target menu has a lot of options, but for total coverage choose All Polygons. Click and drag as before to add the cubes to the mesh. You should now have an even pattern of cubes covering your base mesh.