Glyfada
From Athens Airport, you can take the blue Metro Line 3 with one transfer at Syntagma to the red Line 2 until the Elleniko station. From there, it’s just a short distance (perhaps by taxi) to the bay. You can tell the taxi driver the beach restaurant Maistros. We would then board the dinghy at this spot (you’ll get your feet wet).
There is an option to get into the dinghy dry: You can then tell the taxi driver the restaurant Lasithi. We would then board the dinghy at this spot.