1. Click Shape in the main tool palette.
2. Click Cube in the lower tool palette.
3. Name the object. Naming objects now makes them easier to select from the command line. This is nice when dealing with a large scene.
4. Set the U Step, V Step, Width (x), Height (y) and Length (z) parameters as desired.
5. Click OK to create the shape, or click Cancel to abort.

Cube Options:

U Step - The number of vertices along the u-axis The minimum number is 4.
V Step - The number of vertices along the v-axis. The minimum number is 1.
Width (x) - The width (left to right) of the finished cube.
Height (y) - The height (top to bottom) of the finished cube.
Length (z) - The depth (front to back) of the finished cube.