If we think of ‘basic Jin’ as being the ability to direct the solidity of the ground through the body, from the feet up to the hands, then there are four basic directions we can use this power in.

• Up
• Down
• Away from the body
• Towards the body

And since you can go away from the body and towards the body on both the x and z axis (to the sides and in front and behind), that makes 6 directions in total.

Here’s Mike Sigman explaining the 6 directions and Jin: