I would add to your list: If you don't dive often, do a refresher or warmup in a pool, and run through your emergency procedures before your trip. Things you haven't thought about in years are not going to be in the forefront of your mind if you have a problem.
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Lynn,
Quite agree.
To my daughter's chagrin (less so as she matures), I am a stickler for safety. Having spent 30+ years in EMS (various forms, now in ED) and a wife in ICU nursing 30+ years - she didn't stand a chance
Each year, beginning of summer dive season, we spend 2-3 hours in quarry/pool/lake/wherever we can find just going over basic skills. She is REQUIRED to demonstrate basic skills, i.e. mask clearing/removing/replacing, shooting a SMB at safety stop, sharing air, swimming while breathing her octopus and AIR II, etc.
I noticed this year that she is practicing helicopter turns, frog kicks, etc. on her own.
Now, things are becoming second-nature and I have noticed her taking more initiative and doing her pre-dive checks regardless who she is with. Even to the point of me "arguing the absurd" with her, forcing her to think through her responses and defending her thoughts/actions.
In another time, this might be considered a "mentor".
I would encourage EVERYONE to work the basics (since everything is based off). One of the incidents listed in the Accident forum (~ couple of months ago maybe??) dealt with a diver who jumped in over-weighted with air OFF (IIRC). BASICS FOLKS!
As I told a neurosurgeon who was upset that I "screwed up his neurological assessment" when I chemically paralyzed a trauma victim to gain an airway, "If I didn't get a good airway, you wouldn't have to worry about your neurological assessment!" BASICS FOLKS!!
Practice does NOT make perfect! PERFECT PRACTICE MAKES PERFECT!
My planning (recreational) tends to be a 1:1 (plan-dive) ratio.