The hardest pose in my classes is not the arm balance. It is the ten minutes of lying still at the end, doing nothing at all on purpose.
Rest is not the absence of effort. It is a skill, and skills are built the same slow way — by repetition, without judgement.
Start with three minutes flat on the floor, one hand on the ribs, and no agenda. If your mind writes shopping lists, let it. Staying is the practice, not silence.