Ornos was the ideal beach location you would imagine. Nice sandy, mildly sunny, not cold, shallow blue waters, perfectly clean, very less crowd, beach reclines with cushions and fantastic mountain views around.
We relaxed here for a long time, while the kid could comfortably plan in the water.
Subsequnenly we took a mini boat and went to Platis Gialos beach. This one was lot more crowded and beach front reclines are all owned by hotels along side. We didnt like this one much.
You can take a bus ride back to mykonos town.