This practice can help us interrupt our habitual reactions to certain thoughts.

Write the thought down.

Sit with this thought, observing it.

What feelings/emotions arise?  (Write them down)

What sensations can you feel? (Write them down)

What other thoughts arise ? (Write them down)

Draw a line under what you have written.
Take a deep breath and start again

Write the original thought down and once again be with this thought,
exploring and write down the bodily sensations, emotions and related thoughts.  

Draw a line under what you have written.

And then repeat the process a third time. 

Notice what happens as we revisit this thought with awareness.