Kalvin RitterKalvin Ritter goes to bar on floor 1 at the beginning, then stands on bar on floor 2. After meeting with Terry Norfolk, he start alternating between the bar on floor 2 and his cabin.
Related Challenge: Not For Human Consumption
Go to the right, pick a door with a lockpick and go there. Find the poison and crew disguise on floor 0. After that, see which glass Ritter drinks from at floor 2 and poison it. Beware, since he can spot you. He will then go too restroom near his cabin, where you can drown him.
Related Challenge: Private Meeting
Again, find poison and crew disguise. Poison the drink on bar on floor 1 after Kalvin Ritter drinks from it. Wait until Terry Norfolk comes and drinks it, and then knock him out in the restroom. Disguise as him and talk to the guard near the bar. Follow him and talk to the target. Follow him into his cabin and knock him out.
Related Challenge: Only Use in Emergency Situations
Before meeting with Norfolk, target can stand under the liferaft. Take a crowbar and go to the roof. Knock the guard out and make the liferaft fall. Aternatively, you can do it while the guard isn't looking at it.
Now you're free to either leave upstairs where there is a (makeshift) Helicopter, or you may retrace your steps back downstairs to retrieve your suit, and escape via the Jetski docked at the back of the yacht (near the walkway), or at the Car located at the starting point.
Congratulations, training is over. The final test awaits.