Launching is the same as fresh water.
However, when you have finished and pull the boat out I always thoroughly wash down the boat and trailer, paying particular attention to cleaning the brakes with fresh water. Then I lower the leg and flush the engine out with fresh water using muffs. Make sure you have your fresh water going flat-out before you start the engine up, and run it until the thermostat opens (temp goes to approx 175 degrees) and you can feel the outlet water go warm. Then I switch on the Salt Away mixture. This neutralises salt and leaves a protective coating inside the engine. When I see the water coming out begin foaming, I switch the engine off and the water off. I then reverse it in my garage, unhitch, drop the leg down, then have a well earned beer!
That's it for me...