When working with families in the Family Editor, you can sketch a 2D profile to create an extrusion.
This video demonstrates the following:
An extrusion form is defined as a 2D outline or profile that is pushed or pulled through space to create a 3D form. To create an extrusion, select the Extrusion command. You are placed into sketch mode so the 2D shape can be drawn. Select the sketching tool from the Draw panel. On the Options bar or on the Properties palette, set the depth of the extrusion. You may also change the work plane you are sketching on by using the Set command, if necessary.
A 2D shape is then sketched. The sketch must form a closed loop. If an additional loop is added inside the first one, it will create a hole in the form. Once the sketch is complete, finish the sketch. The form is created at the depth specified.
Control grips can be used to alter the depth or the face position of the completed form. If the profile needs to be changed, click Edit Extrusion on the ribbon. You will be returned to a sketch mode and the 2D profile can be modified. Material can be defined or visibility parameters set on the Properties palette.