A beach day in Poole is easy to get right and surprisingly easy to get wrong, and the difference is almost entirely about timing.
Arrive early
Before about 10am on anything resembling a hot day. Car parks at Sandbanks and the chines fill by mid-morning, and after that you will spend an hour circling. The bus from town is frequently faster door to door.
Pick the right beach
Sandbanks for facilities and lifeguards. Branksome Chine for room and shade from the wooded valley behind. Branksome Dene for quiet. Hamworthy Park for small children, because it faces into the harbour and the water is shallow and calm.
Swim between the flags
RNLI lifeguards patrol the main beaches in season. Red and yellow flags mark the patrolled area. A red flag means do not enter the water. And do not swim in the harbour entrance beside Sandbanks: the tide runs hard through that gap. See beach safety.
When the sand gets too hot
Walk up the chine into the trees. Take a boat trip from the Quay. Or roll onto the chain ferry and spend the afternoon at Studland instead.
Consider a beach hut
Somewhere to change, somewhere dry for your things, and a kettle. It changes a British beach day more than it sounds, and it is arguably best value in spring and autumn. See beach hut hire.
Watch the inflatables
An offshore breeze will take an inflatable out faster than you can swim. It is the most common cause of rescues on this coast.