Entry 1 Pack for the conditions you'll return in, not just depart in
Temperature and wind both tend to shift over the course of a day on open water, often dropping noticeably by late afternoon even on a warm morning. A light layer that seemed unnecessary at departure is frequently the thing someone is glad to have by the trip back.
Entry 2 Waterproofing is about more than a dry bag
Electronics, wallets, and anything else that shouldn't get wet deserve a dedicated waterproof case, but it's worth also thinking about where that case lives during the day — a dry bag left loose on a seat can still end up soaked by spray or a sudden wave.
Entry 3 The things people forget until they need them
Sun protection reapplied partway through the day, enough drinking water for everyone aboard, and a basic first-aid kit are the three items most commonly packed thin or skipped entirely, usually because the day started mild and the need wasn't obvious at the dock.
Entry 4 Questions people ask
How much water is enough for a full day out?
More than feels necessary at the dock — heat, sun, and wind all increase dehydration faster on the water than most people expect.
Is a dry bag enough protection for a phone?
A quality waterproof case or pouch is safer than a standard dry bag alone if the phone will be handled frequently during the trip.