In the waking state, do not mistake yourself to be the body mind sensations and perceptions.
Recognize yourself to be beyond the mind images and bodily sensations.
When you rely on the images and sensations to define you, you have defined yourself according to what is transient and impermanent and therefore you fear change as well as your own imagined ending.
But once you remain in the recognition that you are the aware presence and not what appears, then, and only then, change does not affect you and you remain as the beyond, as the Self eternal and infinite.