The dunes backing the golf club you may want to avoid. Group sex is a common sight along with other exhibitionism.
Plenty of sand. sun beds and parasols for rent (I don't know the cost). Take the road to the beach, it runs parallel to the dry river bed, golf driving range on your left. Easily found as the light-house nearby is readily visible to the right; a little further to the right is the glitzy shopping mall. The photo's are not the best quality as I'd left my camera in the car at Stansted airport and used my £12 phone camera. Copious apologies.