#####Receiver:
rednet.open(...)

function lightsOn()
  rs.setOutput("right", true)
end
function lightsOff()
  rs.setOutput("right", false)
end
function detectSignal()
  event,id,message = os.pullEvent()
  if event == rednet_message and id == 1 then
    if message == "On" then
      lightsOn()
    elseif message == "Off" then
      lightsOff()
    end
  end
end
while true do
  detectSignal()
end

#####Sender:
rednet.open(...)

while true do
  term.clear()
  term.setCursorPos(1,1)
  print("Would you like to switch the lights on or off?")
  input = read()
  if input=="On" or input=="Off" then
    rednet.send(0, input)
  else
    print("Please use only 'On' and 'Off'.")
  end
end