When everything is lined up properly, start the bike and drive it quickly up the ramp, stepping smartly aboard while holding it upright.
I secure the bike to the port side shrouds, and cover it with a tarpaulin to keep spray off. In heavy seas this area can get very wet, and salt water is not good for bikes. I have not had the motorcycle aboard in these conditions but I used to keep a bicycle there and it was seriously degraded by the experience. Now I keep it across the stern, but that's not an option for the motorcycle (unless I built a special rack for it).