Entry 1 What a real float plan includes
A useful float plan covers more than "going out for a few hours" — it names who is aboard, the planned route, the expected return time, a description of the boat, and what to do if you are overdue. Vague version of any of these make it far less useful if it is ever actually needed.
Entry 2 Leave it with someone who will actually act on it
A float plan texted to a friend who is also out for the day and won't check their phone is not much better than no plan at all. The person holding it needs to be reachable and willing to raise an alarm if you are significantly overdue.
Entry 3 Update it if the plan changes
A route or return time that changes after departure should be relayed if there is any way to do so, because a float plan that no longer matches reality can send a search effort to the wrong place or trigger one needlessly.
Entry 4 Questions people ask
Is a float plan necessary for a short trip close to shore?
It is lower-stakes but still worthwhile — most incidents that matter happen quickly and close to normal routes, not only on long offshore trips.
What should the plan-holder do if I'm late?
Give a reasonable buffer for normal delays, then contact you directly, then escalate to local authorities if there is still no contact after a further delay.