How to make x-axis mirror work on newly created bones? (2.79) I'm rigging a model from scratch, but I'm not sure how to make it detect two bones as the "same" one, so that when I transform one bone (in edit mode) it transforms both. How do I make it so that it sees the bones that way? Is there a specific way in which I need to create the bones, or is there a shortcut I can use, or something else?

Example of it not working:
In order for the Mirror Option to know what it should mirror, you need to name the bones according to some guidelines on the wiki (https://docs.blender.org/manual/en/latest/animation/armatures/bones/editing/naming.html). There are also Tools to for example flip the side in the name or mirror bones and their names. You find them in the Armature Menu > Names.