Extrude

Extruding can be done on lines, curves, or faces. An extrusion is specified by a vector:

extrude <x> <y> <z>
extrude <faceNum> <x> <y> <z>
First draw a curve while in insert mode (hit the i key). Complete the curve by hitting right click, or enter.
Extrude - www.vim3d.com

Then extrude the line.

extrude <x> <y> <z>

Extrude - www.vim3d.com

Now turn on face numbers to determine which face to extrude.

view fnums

Extrude - www.vim3d.com

Pick a face and specify the vector.

extrude <faceNum> <x> <y> <z>

Extrude - www.vim3d.com