Concur with most of the above:
Seat belts: definitely keep locked.
Disorientation hand remains on QRB, and (if pax) other hand on escape handle(door handle) - DONT LET GO until all motion has ceased.
DO NOT inflate Mae West inside cockpit!
Most light twins (2-3 tonnes) are estimated to sink at 8'/second
Most roll over (due to high C of G) and rotate through the fore/aft plane (i.e. nose dive)
Dunker is the most valuable form of insurance and should be repeated often (2-3 yearly?).
DONT buy STASS or HEEDS from your corner shop and stick it in your pocket while flying over water!!! You MUST do a training course for this as it is compressed gas at depth. Use it without training and pulmunary embolisms will get you if drowning doesn't
If you think sea floats will keep you upright in anything other than mill pond conditions...think again
Autorotating into water with the engine(s) off will almost certainly take your TR out, unless of course you flare too early
A powered approach to the hover then settling vertically into the water just after the swell is the aim...and that requires precision