Put water in the Instant Pot and then put in the steamer rack making sure the handles are extended up.
Place salmon, skin down on rack.
Drizzle salmon with lemon juice and cover with capers, rosemary and lemon slices.
Close the Instant Pot and make sure vent is turned to “Sealing”. Plug it in, press “Steam” and press the + or – buttons to set it to 3 minutes..
When the Instant Pot beeps that it’s done, quick release the pressure, being careful to stay out of the way of the steam that will shoot up. Press the “Warm/Cancel” button. Remove lid, and using hot pads, carefully remove rack with salmon and set on a plate.
Serve salmon, with lemon and rosemary garnish