Draw a small oval or circle for the base
Sketch a tall vertical stem shape above the base
Add one or more side arms branching from the main stem
Round the tops and edges of each cactus section
Connect the shapes smoothly
Add short curved lines for cactus ridges
Draw small spines along the ridges
Add a pot or ground line if desired
Outline the final shape with a darker line
Erase extra sketch marks
Color the cactus green
Shade one side for depth
Add a brown pot or sandy ground if included