I've been rigging my own models and lately I see a lot of models with weird outlines instead of the normal bones I use.(Like the ones shown below) How do I make these?
You can custom your bones. Create the new shape you want to see as bone, for example a circle. Then select your armature, go in Object or Pose mode, then Properties panel > Bone > Viewport Display, and select the object you've created. If you enable the Wireframe option you'll only see a wireframe object like in your picture.