In ancitipation to Ludum Dare this Saturday. This was frustrating. Hopefully, I won’t forget it anymore.
Process
- Extend from the tail of the leg bone
 - Clear parent (ALT+P)
 - Add pole target (add 3D cursor and then SHIFT+A to add a bone)
 

- Uncheck Deform from Pole Target
 - Go to Pose Mode, select FIRST the IK bone, then the leg bone
 - Then SHIFT+CONTROL+C and choose IK
 - Select the leg bone and adjust the IK constraint values
 


- If the bones are not rotating when moving the IK, reset the chain length.
 
Parenting and Assigning Bones
- Symmetrize the armature in edit mode (select all bones first)
 - Object mode, select the mesh/human/whatever, then shift+click armature
 - CTRL+P and choose with weights or empty groups
 
							
