The habits of aversion and ill will are deep, swift to arise, and often unconscious. One can be already deeply caught up in fighting the upset without knowing when or how the fight started!
Coupled with mindful attention to what is happening, the simple practice of saying "yes" to experiences as you become aware of them can release you from the deep habits of reactive aversion, and help you stay connected to the present moment.
The instructions are simple: As you are practicing mindfulness formally or informally, and you notice any pain or resistance arising, name the pain or upset that is present, and respond with a friendly "yes" to that experience, as if talking to it directly.
For example: "Fear about my health...yes!" "Pain in my tooth...yes!" "Anxiety and worry about my job...yes!"
You may want to try this in informal practice (the situations of daily life). For example: "Stuck in traffic, not moving...yes!" "Angry about what my coworker just said...yes!" "Frightened by the people walking toward me...yes!"
A practical note: saying "yes" to experience assumes you have done or will do what needs to be done as a skillful response. It does not mean being a doormat.
The "yes" practice is a way for you to activate openheartedness as you pay attention moment by moment. Being mindful—noticing what is happening as it is happening—implies making space, being accepting, and not becoming lost in aversion and reactivity. By saying "yes" to experience, you can release the habits of judging and striving for something else, and thus taste true mindfulness more deeply.
Dr. Jeffrey Brantley, 2007 MBSR Conference, Worcester, Massachusetts