Listening to your body's cues and checking in on whether you're able to resolve the physical symptoms of emotional overwhelm are major components of self-regulation. Well + Good's resident neuroscientist Dr. Caroline Leaf recommends breathing exercises, attempting to slow your heart rate, moving your body, or reading aloud to practice self-regulation. Psychology Today describes this process as becoming a "clear channel" — someone who is able to hold others experiencing a dysregulated state without inserting their own emotions or reactions.
Once you are in a regulated state, you can face your partner's acute feelings of stress or emotional overwhelm. And by paying attention to your partner and centering communication, you should be able to discern whether or not they could benefit from co-regulation practices. Dr. Leaf points to mirror neurons in the brain as the reason we are able to affect others with our own state of regulation, so completing physically grounding exercises together may be the easiest way to approach a partner's agitation, and safe touch with permission can also help. One study asserts that even simple guided changes in movement and posture can activate mirror neurons in another person and aid in emotional regulation.
Relationship Restoration notes that we are often unconsciously co-regulating or affecting our partner's emotional and physiological state. However, we can also dysregulate our partners when our own nervous systems enter fight, flight, or freeze mode.