The Bone Tool

Select all of the parts of the arm then make it a movie clip named Arm.

arm whole

Double click on the arm to edit it.

Select the bone tool, bone
then click the top of the arm, the shoulder first. The first place you click will be the anchor.

add the bone tool

Next click the top of the lower arm, then the hand. After you have selected the three joints of the arm, click the selection tool.selection tool

Grab the hand and move it around. The arm bends at the joints but it stays connected.

arm bending

NEXT: Runtime Bones