The above person is correct. There is a podium that has 2 persons there to check you in. I believe that its 8 euro per person for a chair. Bring your towel from your hotel and you're set. It's worth it!
As you walk along the path parallel to the beach, there will be a booth (several, in fact). Some are selling day trips to various Amalfi Coast locations, but one - marked Incanto - sells loungers. Have fun!
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