How to extrude off a surface in Blender

How to extrude?

1) Click on an object

2) Go to Edit Mode

3) Select 'Face Mode' right here, then, click on the surface where you want to extrude the object from.

Alternatively, you can press Ctrl + 3 to select 'Face Mode'.

4) Press 'E' to extrude. 

How to reduce the size of the extruded object?

1) Select the face you want to extrude from

2) Press 'E', then press 'S'

3) Press 'E'