Remove the old dishwasher soap door if applicable. To remove, insert a flat-head screwdriver under the door, and pry off the door. The door pops right off of the dispenser.
Hold the new door face-down above the soap dispenser, and then slide the spring connected to the blue plastic door release onto the spring post on the inside of the soap dispenser door panel.
Align the new door with the edges of the soap dispenser, and then apply downward pressure on the door to snap it onto the dispenser.