I also like Master Lin's reminders to us to smile into our organs and visualise them as being happy, healthy and shining with beautiful colours.
With the kidney and fear specifically, I imagine the fear turning into smoke and coming out of my body. I then imagine the kidneys shining with beautiful blue colours, very plump and healthy and wriggling with happiness and I hold thoughts of gentleness in them.
I also use the self-concentration meditation to assist with all of the other organs in my bod .
For example - getting stronger energy is where there is a blockage (anger) in the liver. I imagine the anger turning into smoke and coming out of my body, going back to the universe. I then see my liver wrapped in a beautiful green colour, shining brightly and very healthy and hold strong thoughts of kindness and forgiveness in the liver area
Love
Jetay.