Gil Fronsdal leads an Anapanasati Reassurance of the Breath. There's a saying- to breath at ease is closely related to the feeling of reassurance.
Notice how you're breathing. Pay attention to your breathing. Without any judgement or any idea it should be any different, what should it feel like to be breathing right now?
Would you characterize your breathing as being at ease or is your breathing not so much at ease?
And as you experience your breathing, where are the locations in your body that you feel the sensations in your body that you feel at ease. Where in your body you feel the breathing is easeful and where it's not as easeful.
And if there's some places that breathing doesn't feel easeful, stay with it, stay with that place, let the rhythm of breathing be some kind of a massage.
And then as you exhale in a very gentle simple way, let your body relax. Especially let there be relaxation and softness in the parts of your body that move as you breathe.