An invitation, not a prescription. You don't need a cushion, a script, or a quiet room. You need ten minutes and a floor.
Lie down. On your back, on the floor — not the bed. Knees bent or legs up the wall, whichever feels easier on your lower back.
One hand on the belly. See whether the breath wants to move there. If only the chest is moving, notice that too — that's information, not a failure.
In through the nose for 4. Out through the nose for 6. No force. Soft jaw, soft shoulders. If 6 feels long, try 5. The numbers are scaffolding, not a test.
Ten minutes. Then notice — what's different, what isn't, what surprised you. Different bodies have different conversations with this practice. The point isn't to arrive somewhere specific. It's to listen to what arrives.
A note: if any of this feels activating rather than settling, ease the ratio (4 in, 5 out), open your eyes, and shorten the practice. Your system is allowed to be picky. Different techniques meet different people in different ways.