Pop the door or window prior to impact
I'll not comment on the rest of this thread as there's a ton of ditching information on ETS, but the following information is potentially very critical and just now becoming more widely known:
IF YOU FLY COLUMBIA AIRCRAFT, DO NOT OPEN THE DOOR IN FLIGHT! (Other aircraft with gull wing doors may also be at risk. Always check your Pilot's Operating handbook to ensure that opening the door is safe to do.)